diff --git a/mozilla/toolkit/mozapps/update/src/nsUpdateService.js.in b/mozilla/toolkit/mozapps/update/src/nsUpdateService.js.in
index ef7bbe53b8d..58d317e5645 100644
--- a/mozilla/toolkit/mozapps/update/src/nsUpdateService.js.in
+++ b/mozilla/toolkit/mozapps/update/src/nsUpdateService.js.in
@@ -1022,18 +1022,26 @@ function UpdateService() {
     LOG("UpdateService", "XPCOM ABI unknown: updates are not possible.");
   }
 
+  var osVersion;
+  var sysInfo = Components.classes["@mozilla.org/system-info;1"]
+                          .getService(Components.interfaces.nsIPropertyBag2);
   try {
-    var sysInfo =
-      Components.classes["@mozilla.org/system-info;1"]
-                .getService(Components.interfaces.nsIPropertyBag2);
-
-    gOSVersion = encodeURIComponent(sysInfo.getProperty("name") + " " +
-                                    sysInfo.getProperty("version"));
+    osVersion = sysInfo.getProperty("name") + " " + sysInfo.getProperty("version");
   }
   catch (e) {
     LOG("UpdateService", "OS Version unknown: updates are not possible.");
   }
 
+  if (osVersion) {
+    try {
+      osVersion += " (" + sysInfo.getProperty("secondaryLibrary") + ")";
+    }
+    catch (e) {
+      // Not all platforms have a secondary widget library, so an error is nothing to worry about.
+    }
+    gOSVersion = encodeURIComponent(osVersion);
+  }
+
 #ifdef XP_MACOSX
   // Mac universal build should report a different ABI than either macppc
   // or mactel.
diff --git a/mozilla/xpcom/base/Makefile.in b/mozilla/xpcom/base/Makefile.in
index 4b95919ae92..4213020a66a 100644
--- a/mozilla/xpcom/base/Makefile.in
+++ b/mozilla/xpcom/base/Makefile.in
@@ -148,3 +148,7 @@ include $(topsrcdir)/config/rules.mk
 
 DEFINES		+= -D_IMPL_NS_COM
 
+ifneq (,$(filter gtk2,$(MOZ_WIDGET_TOOLKIT)))
+CXXFLAGS        += $(MOZ_GTK2_CFLAGS)
+endif
+
diff --git a/mozilla/xpcom/base/nsSystemInfo.cpp b/mozilla/xpcom/base/nsSystemInfo.cpp
index c93a9310a66..821370457e7 100644
--- a/mozilla/xpcom/base/nsSystemInfo.cpp
+++ b/mozilla/xpcom/base/nsSystemInfo.cpp
@@ -39,6 +39,11 @@
 #include "nsSystemInfo.h"
 #include "prsystem.h"
 #include "nsString.h"
+#include "prprf.h"
+
+#ifdef MOZ_WIDGET_GTK2
+#include <gtk/gtk.h>
+#endif
 
 nsSystemInfo::nsSystemInfo()
 {
@@ -74,6 +79,17 @@ nsSystemInfo::Init()
       else
         NS_WARNING("PR_GetSystemInfo failed");
     }
+
+#ifdef MOZ_WIDGET_GTK2
+    // This must be done here because NSPR can only separate OS's when compiled, not libraries.
+    char* gtkver = PR_smprintf("GTK %u.%u.%u", gtk_major_version, gtk_minor_version, gtk_micro_version);
+    if (gtkver) {
+      rv = SetPropertyAsACString(NS_ConvertASCIItoUTF16("secondaryLibrary"),
+                                 nsDependentCString(gtkver));
+      PR_smprintf_free(gtkver);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+#endif
    
     return NS_OK;
 }
diff --git a/mozilla/xpcom/build/Makefile.in b/mozilla/xpcom/build/Makefile.in
index 791bc6a137c..4532896a0b9 100644
--- a/mozilla/xpcom/build/Makefile.in
+++ b/mozilla/xpcom/build/Makefile.in
@@ -186,6 +186,10 @@ ifeq ($(OS_ARCH),BeOS)
 EXTRA_DSO_LDOPTS += -lbe
 endif
 
+ifneq (,$(filter gtk2,$(MOZ_WIDGET_TOOLKIT)))
+EXTRA_DSO_LDOPTS += $(MOZ_GTK2_LIBS)
+endif
+
 ifeq ($(OS_ARCH),WINNT)
 EXTRA_DSO_LDOPTS += $(call EXPAND_LIBNAME,shell32 ole32 uuid version)
 ifneq (,$(MOZ_DEBUG)$(NS_TRACE_MALLOC))