diff --git a/Source/WebCore/plugins/qt/PluginPackageQt.cpp b/Source/WebCore/plugins/qt/PluginPackageQt.cpp
index a923d49aa..46772a4bb 100644
--- a/Source/WebCore/plugins/qt/PluginPackageQt.cpp
+++ b/Source/WebCore/plugins/qt/PluginPackageQt.cpp
@@ -136,7 +136,11 @@ static void initializeGtk(QLibrary* module = 0)
         }
     }
 
+#ifdef NIXPKGS_LIBGTK2
+    QLibrary library(QLatin1String(NIXPKGS_LIBGTK2), 0);
+#else
     QLibrary library(QLatin1String("libgtk-x11-2.0"), 0);
+#endif
     if (library.load()) {
         typedef void *(*gtk_init_check_ptr)(int*, char***);
         gtk_init_check_ptr gtkInitCheck = (gtk_init_check_ptr)library.resolve("gtk_init_check");
diff --git a/Source/WebCore/plugins/qt/PluginViewQt.cpp b/Source/WebCore/plugins/qt/PluginViewQt.cpp
index de06a2fea..86fe39ef1 100644
--- a/Source/WebCore/plugins/qt/PluginViewQt.cpp
+++ b/Source/WebCore/plugins/qt/PluginViewQt.cpp
@@ -697,7 +697,11 @@ static Display *getPluginDisplay()
     // support gdk based plugins (like flash) that use a different X connection.
     // The code below has the same effect as this one:
     // Display *gdkDisplay = gdk_x11_display_get_xdisplay(gdk_display_get_default());
+#ifdef NIXPKGS_LIBGDK2
+    QLibrary library(QLatin1String(NIXPKGS_LIBGDK2), 0);
+#else
     QLibrary library(QLatin1String("libgdk-x11-2.0"), 0);
+#endif
     if (!library.load())
         return 0;
 
diff --git a/Source/WebKit2/PluginProcess/qt/PluginProcessMainQt.cpp b/Source/WebKit2/PluginProcess/qt/PluginProcessMainQt.cpp
index 8de65216b..38f5c05e5 100644
--- a/Source/WebKit2/PluginProcess/qt/PluginProcessMainQt.cpp
+++ b/Source/WebKit2/PluginProcess/qt/PluginProcessMainQt.cpp
@@ -53,7 +53,11 @@ static void messageHandler(QtMsgType type, const QMessageLogContext&, const QStr
 
 static bool initializeGtk()
 {
+#ifdef NIXPKGS_LIBGTK2
+    QLibrary gtkLibrary(QLatin1String(NIXPKGS_LIBGTK2), 0);
+#else
     QLibrary gtkLibrary(QLatin1String("libgtk-x11-2.0"), 0);
+#endif
     if (!gtkLibrary.load())
         return false;
     typedef void* (*gtk_init_ptr)(void*, void*);
diff --git a/Source/WebKit2/WebProcess/Plugins/Netscape/x11/NetscapePluginX11.cpp b/Source/WebKit2/WebProcess/Plugins/Netscape/x11/NetscapePluginX11.cpp
index d734ff684..0f6ff63d1 100644
--- a/Source/WebKit2/WebProcess/Plugins/Netscape/x11/NetscapePluginX11.cpp
+++ b/Source/WebKit2/WebProcess/Plugins/Netscape/x11/NetscapePluginX11.cpp
@@ -64,7 +64,11 @@ static Display* getPluginDisplay()
     // The code below has the same effect as this one:
     // Display *gdkDisplay = gdk_x11_display_get_xdisplay(gdk_display_get_default());
 
+#ifdef NIXPKGS_LIBGDK2
+    QLibrary library(QLatin1String(NIXPKGS_LIBGDK2), 0);
+#else
     QLibrary library(QLatin1String("libgdk-x11-2.0"), 0);
+#endif
     if (!library.load())
         return 0;