diff --git a/zenmap/radialnet/gui/RadialNet.py b/zenmap/radialnet/gui/RadialNet.py
index 3523b0414..eb0e8acfb 100644
--- a/zenmap/radialnet/gui/RadialNet.py
+++ b/zenmap/radialnet/gui/RadialNet.py
@@ -1851,29 +1851,19 @@ class NetNode(Node):
                 if host.uptime.get("seconds") or host.uptime.get("lastboot"):
                     return host.uptime
             elif info == "device_type":
-                if len(host.osclasses) == 0:
+                osmatch = host.get_best_osmatch()
+                if osmatch is None:
+                    return None
+                osclasses = osmatch['osclasses']
+                if len(osclasses) == 0:
                     return None
                 types = ["router", "wap", "switch", "firewall"]
                 for type in types:
-                    if type in host.osclasses[0].get("type", "").lower():
+                    if type in osclasses[0].get("type", "").lower():
                         return type
             elif info == "os":
                 os = {}
 
-                os_classes = []
-                for osclass in host.osclasses:
-                    os_class = {}
-
-                    os_class["type"] = osclass.get("type", "")
-                    os_class["vendor"] = osclass.get("vendor", "")
-                    #os_class["accuracy"] = int(osclass.get("accuracy", ""))
-                    os_class["accuracy"] = osclass.get("accuracy", "")
-                    os_class["os_family"] = osclass.get("osfamily", "")
-                    os_class["os_gen"] = osclass.get("osgen", "")
-
-                    os_classes.append(os_class)
-                os["classes"] = os_classes
-
                 # osmatches
                 if len(host.osmatches) > 0 and \
                    host.osmatches[0]["accuracy"] != "" and \
@@ -1883,6 +1873,20 @@ class NetNode(Node):
                     os["matches"] = host.osmatches
                     os["matches"][0]["db_line"] = 0     # not supported
 
+                    os_classes = []
+                    for osclass in host.osmatches[0]["osclasses"]:
+                        os_class = {}
+
+                        os_class["type"] = osclass.get("type", "")
+                        os_class["vendor"] = osclass.get("vendor", "")
+                        #os_class["accuracy"] = int(osclass.get("accuracy", ""))
+                        os_class["accuracy"] = osclass.get("accuracy", "")
+                        os_class["os_family"] = osclass.get("osfamily", "")
+                        os_class["os_gen"] = osclass.get("osgen", "")
+
+                        os_classes.append(os_class)
+                    os["classes"] = os_classes
+
                 # ports_used
                 if len(host.ports_used) > 0:
                     if os == None:
diff --git a/zenmap/radialnet/util/integration.py b/zenmap/radialnet/util/integration.py
index 6561ae933..88be49d42 100644
--- a/zenmap/radialnet/util/integration.py
+++ b/zenmap/radialnet/util/integration.py
@@ -125,12 +125,21 @@ class TracerouteHostInfo(object):
         self.hostname = None
         self.ports = []
         self.extraports = []
-        self.osclasses = []
         self.osmatches = []
 
     def get_hostname(self):
         return self.hostname
 
+    def get_best_osmatch(self):
+        if not self.osmatches:
+            return None
+        def osmatch_key(osmatch):
+            try:
+                return -float(osmatch["accuracy"])
+            except ValueError:
+                return 0
+        return sorted(self.osmatches, key = osmatch_key)[0]
+
     hostnames = property(lambda self: self.hostname and [self.hostname] or [])
 
 def make_graph_from_hosts(hosts):
diff --git a/zenmap/zenmapCore/NetworkInventory.py b/zenmap/zenmapCore/NetworkInventory.py
index 202a1b719..dc286626f 100644
--- a/zenmap/zenmapCore/NetworkInventory.py
+++ b/zenmap/zenmapCore/NetworkInventory.py
@@ -257,8 +257,7 @@ class NetworkInventory(object):
         # OS detection fields
         # Replace old_host's OS detection fields with new_host's if old_host has no
         # OS detection info or new_host's info is newer.
-        if len(new_host.osclasses) > 0 and (len(old_host.osclasses) == 0 or old_date < new_date):
-            old_host.osclasses = new_host.osclasses
+        if len(new_host.osmatches) > 0 and (len(old_host.osmatches) == 0 or old_date < new_date):
             old_host.osmatches = new_host.osmatches
             old_host.ports_used = new_host.ports_used
 
@@ -633,7 +632,6 @@ if __name__ == "__main__":
             #for port in host.ports:
             #    print "  %s: %s" % (port["portid"], port["port_state"])
             #print "  OS matches: %s" % host.osmatches
-            #print "  OS classes: %s" % host.osclasses
             #print "  Ports used: %s" % host.ports_used
             #print "  Trace: %s" % host.trace
             #if "hops" in host.trace:
diff --git a/zenmap/zenmapCore/NmapParser.py b/zenmap/zenmapCore/NmapParser.py
index ef9efa1e3..0585ad92c 100644
--- a/zenmap/zenmapCore/NmapParser.py
+++ b/zenmap/zenmapCore/NmapParser.py
@@ -111,13 +111,12 @@ from zenmapCore.NmapOptions import NmapOptions, split_quoted, join_quoted
 from zenmapCore.StringPool import unique
 
 # The version of the Nmap DTD this file understands and emits.
-XML_OUTPUT_VERSION = "1.03"
+XML_OUTPUT_VERSION = "1.04"
 
 class HostInfo(object):
     def __init__(self):
         self.comment = None;
         self._tcpsequence = {}
-        self._osclasses = []
         self._osmatches = []
         self._ports = []
         self._ports_used = []
@@ -137,8 +136,7 @@ class HostInfo(object):
         clone = HostInfo()
         clone.comment = self.comment
         clone._tcpsequence = copy.deepcopy(self._tcpsequence)
-        clone._osclasses = map(lambda d: copy.deepcopy(d), self._osclasses)
-        clone._osmatches = self._osmatches
+        clone._osmatches = copy.deepcopy(self._osmatches)
         clone._ports = copy.deepcopy(self._ports)
         clone._ports_used = self._ports_used
         clone._extraports = self._extraports
@@ -188,17 +186,12 @@ class HostInfo(object):
             return self._ipidsequence
         return {}
 
-    # osclasses is a list containing dicts of the form
+    # osmatches is a list of dicts of the form
+    # {'name': u'Linux 2.6.24', 'accuracy': u'98', 'line': u'1000',
+    #  'osclasses': ...}
+    # where each 'osclasses' element is a dict of the form
     # {'vendor': u'Linux', 'osfamily': u'Linux', 'type': u'general purpose',
     #  'osgen': u'2.6.X', 'accuracy': u'98'}
-    def set_osclasses(self, classes):
-        self._osclasses = classes
-
-    def get_osclasses(self):
-        return self._osclasses
-
-    # osmatches is a list of dicts of the form
-    # {'name': u'Linux 2.6.24', 'accuracy': u'98', 'line': u'1000'}
     def set_osmatches(self, matches):
         self._osmatches = matches
 
@@ -222,22 +215,6 @@ class HostInfo(object):
         return osmatches[-1]
 
 
-    def get_best_osclass(self):
-        """Return the OS class with the highest accuracy. If there is a tie, one
-        of the best matches will be returned."""
-        if not self._osclasses:
-            return None
-        def osclass_key(osclass):
-            # Sort first by accuracy, then by name so it's deterministic.
-            try:
-                accuracy = float(osclass.get("accuracy", ""))
-            except ValueError:
-                accuracy = 0
-            return (accuracy, osclass.get("name"))
-        osclasses = self.osclasses[:]
-        osclasses.sort(cmp = lambda a, b: cmp(osclass_key(a), osclass_key(b)))
-        return osclasses[-1]
-
     # ports_used is a list like
     # [{'state': u'open', 'portid': u'22', 'proto': u'tcp'},
     #  {'state': u'closed', 'portid': u'25', 'proto': u'tcp'},
@@ -429,7 +406,6 @@ class HostInfo(object):
 
     # Properties
     tcpsequence = property(get_tcpsequence, set_tcpsequence)
-    osclasses = property(get_osclasses, set_osclasses)
     osmatches = property(get_osmatches, set_osmatches)
     ports = property(get_ports, set_ports)
     ports_used = property(get_ports_used, set_ports_used)
@@ -876,7 +852,9 @@ class NmapParserSAX(ParserBasics, ContentHandler):
         self.dic_port["service_extrainfo"] = attrs.get("extrainfo", "")
 
     def _parse_host_osmatch(self, attrs):
-        self.list_osmatch.append(self._parsing(attrs, [], ['name', 'accuracy', 'line']))
+        osmatch = self._parsing(attrs, [], ['name', 'accuracy', 'line'])
+        osmatch['osclasses'] = []
+        self.list_osmatch.append(osmatch)
 
     def _parse_host_portused(self, attrs):
         self.list_portused.append(self._parsing(attrs, ['state', 'proto', 'portid'], []))
@@ -972,12 +950,12 @@ class NmapParserSAX(ParserBasics, ContentHandler):
             self.in_os = True
             self.list_portused = []
             self.list_osmatch = []
-            self.list_osclass = []
         elif self.in_host and self.in_os and name == "osmatch":
             self._parse_host_osmatch(attrs)
         elif self.in_host and self.in_os and name == "portused":
             self._parse_host_portused(attrs)
         elif self.in_host and self.in_os and name == "osclass":
+            self.list_osclass = []
             self._parse_host_osclass(attrs)
         elif self.in_host and name == "uptime":
             self._parse_host_uptime(attrs)
@@ -1015,15 +993,16 @@ class NmapParserSAX(ParserBasics, ContentHandler):
             self.in_port = False
             self.list_ports.append(self.dic_port)
             del(self.dic_port)
+        elif self.in_host and self.in_os and name == "osmatch":
+            self.list_osmatch[-1]['osclasses'].extend(self.list_osclass)
+            self.list_osclass = []
         elif self.in_host and self.in_os and name == "os":
             self.in_os = False
             self.host_info.set_ports_used(self.list_portused)
             self.host_info.set_osmatches(self.list_osmatch)
-            self.host_info.set_osclasses(self.list_osclass)
 
             del(self.list_portused)
             del(self.list_osmatch)
-            del(self.list_osclass)
         elif self.in_host and self.in_trace and name == "trace":
             self.in_trace = False
 
@@ -1213,22 +1192,21 @@ class NmapParserSAX(ParserBasics, ContentHandler):
                                             portid = pu.get("portid", ""))))
                 writer.endElement("portused")
 
-            ## Osclass elements
-            for oc in host.osclasses:
-                writer.startElement("osclass",
-                    Attributes(dict(vendor = oc.get("vendor", ""),
-                                    osfamily = oc.get("osfamily", ""),
-                                    type = oc.get("type", ""),
-                                    osgen = oc.get("osgen", ""),
-                                    accuracy = oc.get("accuracy", ""))))
-                writer.endElement("osclass")
-
             ## Osmatch elements
             for om in host.osmatches:
                 writer.startElement("osmatch",
                     Attributes(dict(name = om.get("name", ""),
                                     accuracy = om.get("accuracy", ""),
                                     line = om.get("line", ""))))
+                ## Osclass elements
+                for oc in om['osclasses']:
+                    writer.startElement("osclass",
+                        Attributes(dict(vendor = oc.get("vendor", ""),
+                                        osfamily = oc.get("osfamily", ""),
+                                        type = oc.get("type", ""),
+                                        osgen = oc.get("osgen", ""),
+                                        accuracy = oc.get("accuracy", ""))))
+                    writer.endElement("osclass")
                 writer.endElement("osmatch")
 
             writer.endElement("os")
@@ -1358,7 +1336,7 @@ if __name__ == '__main__':
         for p in host.ports:
             print "\t%s" % repr(p)
         print "  Ports used:", repr(host.ports_used)
-        print "  OS Class:", repr(host.osclasses)
+        print "  OS Matches:", repr(host.osmatches)
         print "  Hostnames:", repr(host.hostnames)
         print "  IP:", repr(host.ip)
         print "  IPv6:", repr(host.ipv6)
diff --git a/zenmap/zenmapCore/SearchResult.py b/zenmap/zenmapCore/SearchResult.py
index 4324058f8..7ad032080 100644
--- a/zenmap/zenmapCore/SearchResult.py
+++ b/zenmap/zenmapCore/SearchResult.py
@@ -148,15 +148,14 @@ class HostSearch(object):
         os = os.lower()
         os_str = ""
 
-        osclasses = host.get_osclasses()
         osmatches = host.get_osmatches()
 
-        for osclass in osclasses:
-            os_str += osclass['vendor'].lower() + " " +\
-                      osclass['osfamily'].lower() + " " +\
-                      osclass['type'].lower()
         for osmatch in osmatches:
             os_str += osmatch['name'].lower()
+            for osclass in osmatch['osmatches']:
+                os_str += osclass['vendor'].lower() + " " +\
+                          osclass['osfamily'].lower() + " " +\
+                          osclass['type'].lower()
 
         if os in os_str:
             return True
@@ -566,7 +565,6 @@ if __name__ == "__main__":
                              #port_filtered="",
                              #port_closed="",
                              #service="",
-                             #osclass="Microsoft | Windows | 95/98/ME | General Purpose",
                              #osmatch="gentoo",
                              #product="Apache"\
 #                           ):
diff --git a/zenmap/zenmapGUI/Icons.py b/zenmap/zenmapGUI/Icons.py
index 4dfbc9528..e44f35049 100644
--- a/zenmap/zenmapGUI/Icons.py
+++ b/zenmap/zenmapGUI/Icons.py
@@ -148,8 +148,11 @@ if pixmap_path:
     iconfactory.add_default()
 
 def get_os_icon(host):
-    osclass = host.get_best_osclass()
     osmatch = host.get_best_osmatch()
+    if osmatch and osmatch['osclasses']:
+        osclass = osmatch['osclasses'][0]
+    else:
+        osclass = None
 
     if osclass and osmatch:
         return get_os(osclass['osfamily'], osmatch['name'], 'icon')
@@ -157,8 +160,11 @@ def get_os_icon(host):
         return get_os(None, None, 'icon')
 
 def get_os_logo(host):
-    osclass = host.get_best_osclass()
     osmatch = host.get_best_osmatch()
+    if osmatch and osmatch['osclasses']:
+        osclass = osmatch['osclasses'][0]
+    else:
+        osclass = None
 
     if osclass and osmatch:
         return get_os(osclass['osfamily'], osmatch['name'], 'logo')
diff --git a/zenmap/zenmapGUI/ScanHostDetailsPage.py b/zenmap/zenmapGUI/ScanHostDetailsPage.py
index 622b83bb2..83495ba03 100644
--- a/zenmap/zenmapGUI/ScanHostDetailsPage.py
+++ b/zenmap/zenmapGUI/ScanHostDetailsPage.py
@@ -140,7 +140,6 @@ class HostDetails(HIGVBox):
         os = host.get_best_osmatch()
         if os:
             os['portsused'] = host.get_ports_used()
-            os['osclass'] = host.get_osclasses()
 
         self.set_os(os)
         self.set_tcpseq(host.get_tcpsequence())
@@ -154,7 +153,7 @@ class HostDetails(HIGVBox):
         self.hostnames_expander = gtk.Expander('<b>'+_('Hostnames')+'</b>')
         self.os_expander = gtk.Expander('<b>'+_('Operating System')+'</b>')
         self.portsused_expander = gtk.Expander('<b>'+_('Ports used')+'</b>')
-        self.osclass_expander = gtk.Expander('<b>'+_('OS Class')+'</b>')
+        self.osclass_expander = gtk.Expander('<b>'+_('OS Classes')+'</b>')
         self.tcp_expander = gtk.Expander('<b>'+_('TCP Sequence')+'</b>')
         self.ip_expander = gtk.Expander('<b>'+_('IP ID Sequence')+'</b>')
         self.tcpts_expander = gtk.Expander('<b>'+_('TCP TS Sequence')+'</b>')
@@ -368,7 +367,7 @@ class HostDetails(HIGVBox):
             except:pass
 
             try:
-                self.set_osclass(os['osclass'])
+                self.set_osclass(os['osclasses'])
                 self.osclass_expander.set_use_markup(True)
                 table.attach(self.osclass_expander,0,2,y1,y2)
             except:pass