diff --git a/nse_dnet.cc b/nse_dnet.cc
index 685fcbb76..fc1401991 100644
--- a/nse_dnet.cc
+++ b/nse_dnet.cc
@@ -260,7 +260,7 @@ usesock:
     ret = send_ip_packet(udata->sock, NULL, (u8 *) packet, lua_objlen(L, 2));
   }
   if (ret == -1)
-    return luaL_error(L, "error while sending: %s (errno %d)",
+    return safe_error(L, "error while sending: %s (errno %d)",
         socket_strerror(socket_errno()), socket_errno());
 
   return success(L);
diff --git a/nse_utility.cc b/nse_utility.cc
index 4d20e52d1..45e48016a 100644
--- a/nse_utility.cc
+++ b/nse_utility.cc
@@ -1,4 +1,5 @@
 #include <stdlib.h>
+#include <stdarg.h>
 
 #include "Target.h"
 #include "portlist.h"
@@ -57,10 +58,13 @@ int success (lua_State *L)
   return 1;
 }
 
-int safe_error (lua_State *L, const char *message)
+int safe_error (lua_State *L, const char *fmt, ...)
 {
+  va_list va;
   lua_pushboolean(L, false);
-  lua_pushstring(L, message);
+  va_start(va, fmt);
+  lua_pushvfstring(L, fmt, va);
+  va_end(va);
   return 2;
 }
 
diff --git a/nse_utility.h b/nse_utility.h
index 1718b598f..b8d0d7681 100644
--- a/nse_utility.h
+++ b/nse_utility.h
@@ -8,7 +8,7 @@ void setbfield (lua_State *, int, const char *, int);
 void weak_table (lua_State *, int, int, const char *);
 
 int success (lua_State *);
-int safe_error (lua_State *, const char *);
+int safe_error (lua_State *, const char *, ...);
 
 void check_target (lua_State *, int, const char **, const char **);
 unsigned short check_port (lua_State *, int, const char **);