diff --git a/mozilla/aclocal.m4 b/mozilla/aclocal.m4
index a05035902d0..82055d9e6ca 100644
--- a/mozilla/aclocal.m4
+++ b/mozilla/aclocal.m4
@@ -7,6 +7,7 @@ builtin(include, build/autoconf/glib.m4)dnl
 builtin(include, build/autoconf/gtk.m4)dnl
 builtin(include, build/autoconf/libIDL.m4)dnl
 builtin(include, build/autoconf/nspr.m4)dnl
+builtin(include, build/autoconf/pkg.m4)dnl
 dnl
 define(MOZ_TOPSRCDIR,.)dnl MOZ_TOPSRCDIR is used in altoptions.m4
 builtin(include, build/autoconf/altoptions.m4)dnl
diff --git a/mozilla/build/autoconf/pkg.m4 b/mozilla/build/autoconf/pkg.m4
new file mode 100644
index 00000000000..290ee06ab75
--- /dev/null
+++ b/mozilla/build/autoconf/pkg.m4
@@ -0,0 +1,57 @@
+dnl This file is Copyright 2001 Red Hat, Inc.
+dnl This file is in the public domain.
+dnl
+dnl PKG_CHECK_MODULES(GSTUFF, gtk+-2.0 >= 1.3 glib = 1.3.4, action-if, action-not)
+dnl defines GSTUFF_LIBS, GSTUFF_CFLAGS, see pkg-config man page
+dnl also defines GSTUFF_PKG_ERRORS on error
+AC_DEFUN(PKG_CHECK_MODULES, [
+  succeeded=no
+
+  if test -z "$PKG_CONFIG"; then
+    AC_PATH_PROG(PKG_CONFIG, pkg-config, no)
+  fi
+
+  if test "$PKG_CONFIG" = "no" ; then
+     echo "*** The pkg-config script could not be found. Make sure it is"
+     echo "*** in your path, or set the PKG_CONFIG environment variable"
+     echo "*** to the full path to pkg-config."
+  else
+     if ! $PKG_CONFIG --atleast-pkgconfig-version 0.7.0; then
+        echo "*** Your version of pkg-config is too old. You need version 0.7.0 or newer."
+        echo "*** See http://www.freedesktop.org/software/pkgconfig"
+     else
+        AC_MSG_CHECKING(for $2)
+
+        if $PKG_CONFIG --exists "$2" ; then
+            AC_MSG_RESULT(yes)
+            succeeded=yes
+
+            AC_MSG_CHECKING($1_CFLAGS)
+            $1_CFLAGS=`$PKG_CONFIG --cflags "$2"`
+            AC_MSG_RESULT($$1_CFLAGS)
+
+            AC_MSG_CHECKING($1_LIBS)
+            $1_LIBS=`$PKG_CONFIG --libs "$2"`
+            AC_MSG_RESULT($$1_LIBS)
+        else
+            $1_CFLAGS=""
+            $1_LIBS=""
+            ## If we have a custom action on failure, don't print errors, but 
+            ## do set a variable so people can do so.
+            $1_PKG_ERRORS=`$PKG_CONFIG --errors-to-stdout --print-errors "$2"`
+            ifelse([$4], ,echo $1_PKG_ERRORS,)
+        fi
+
+        AC_SUBST($1_CFLAGS)
+        AC_SUBST($1_LIBS)
+     fi
+  fi
+
+  if test $succeeded = yes; then
+     ifelse([$3], , :, [$3])
+  else
+     ifelse([$4], , AC_MSG_ERROR([Library requirements ($2) not met; consider adjusting the PKG_CONFIG_PATH environment variable if your libraries are in a nonstandard prefix so pkg-config can find them.]), [$4])
+  fi
+])
+
+
diff --git a/mozilla/configure.in b/mozilla/configure.in
index 88adb9368fa..4ede1e07199 100644
--- a/mozilla/configure.in
+++ b/mozilla/configure.in
@@ -87,6 +87,7 @@ LIBIDL_VERSION=0.6.3
 PERL_VERSION=5.004
 QT_VERSION=2.2.0
 QT_VERSION_NUM=220
+GTK2_VERSION=1.3.7
 
 dnl Set various checks
 dnl ========================================================
@@ -1154,15 +1155,16 @@ then
 	AC_ARG_ENABLE(toolkit,
 	[  --enable-toolkit=\$val   Enable \$val fe (defaults to gtk)],
 	  [	if test "$enableval" = "motif" \
-	        -o "$enableval" = "gtk" \
-	        -o "$enableval" = "qt" \
-	        -o "$enableval" = "xlib"
+            -o "$enableval" = "gtk" \
+            -o "$enableval" = "qt" \
+            -o "$enableval" = "gtk2" \
+            -o "$enableval" = "xlib"
 		then
 		     dnl nglayout only supports building with one toolkit,
 		     dnl so ignore everything after the first comma (",").
 		     MOZ_WIDGET_TOOLKIT=`echo "$enableval" | sed -e "s/,.*$//"`
 		else
-		     AC_MSG_ERROR(Toolkit must be Xlib, GTK, Qt, or Motif.)
+		     AC_MSG_ERROR(Toolkit must be xlib, gtk, gtk2, qt, or motif.)
 		fi], 
 
 	  [	MOZ_WIDGET_TOOLKIT="gtk" ])
@@ -1306,6 +1308,12 @@ then
 	AC_DEFINE(MOZ_WIDGET_GTK)
 fi
 
+if test "$MOZ_WIDGET_TOOLKIT" = "gtk2"
+then
+    MOZ_ENABLE_GTK2=1
+    AC_DEFINE(MOZ_WIDGET_GTK2)
+fi
+
 if test "$MOZ_WIDGET_TOOLKIT" = "xlib"
 then
 	MOZ_ENABLE_XLIB=1
@@ -1364,7 +1372,6 @@ then
     AM_PATH_GTK($GTK_VERSION,,
       AC_MSG_ERROR(Test for GTK failed.))
 
-
 dnl ========================================================
 dnl =							   =
 dnl = --with-java-supplement				   =
@@ -1461,6 +1468,15 @@ dnl =   order matters to the Build Configurator.           =
 dnl =                                                      =
 dnl ========================================================
 
+dnl ========================================================
+dnl = Gtk2 support
+dnl ========================================================
+
+if test "$MOZ_ENABLE_GTK2"
+then
+    PKG_CHECK_MODULES(MOZ_GTK2, gtk+-2.0 >= 1.3.7)
+fi
+
 dnl ========================================================
 dnl =                                                      =
 dnl = --with-xprint                                        =
@@ -1779,6 +1795,12 @@ then
 	TK_LIBS="$MOZ_GTK_LDFLAGS"
 fi
 
+if test "$MOZ_WIDGET_TOOLKIT" = "gtk2"
+then
+    TK_CFLAGS="$MOZ_GTK2_CFLAGS"
+    TK_LIBS="$MOZ_GTK2_LDFLAGS"
+fi
+
 if test "$MOZ_WIDGET_TOOLKIT" = "xlib"
 then
 	TK_CFLAGS="$MOZ_XLIB_CFLAGS"
@@ -1811,14 +1833,14 @@ AC_SUBST(TK_LIBS)
 AC_SUBST(MOZ_ENABLE_GTK)
 AC_SUBST(MOZ_ENABLE_MOTIF)
 AC_SUBST(MOZ_ENABLE_XLIB)
-AC_SUBST(MOZ_ENABLE_GTK)
-AC_SUBST(MOZ_ENABLE_MOTIF)
-AC_SUBST(MOZ_ENABLE_XLIB)
+AC_SUBST(MOZ_ENABLE_GTK2)
 AC_SUBST(MOZ_ENABLE_QT)
 AC_SUBST(MOZ_ENABLE_PHOTON)
 AC_SUBST(MOZ_ENABLE_XREMOTE)
 AC_SUBST(MOZ_GTK_CFLAGS)
 AC_SUBST(MOZ_GTK_LDFLAGS)
+AC_SUBST(MOZ_GTK2_CFLAGS)
+AC_SUBST(MOZ_GTK2_LDFLAGS)
 AC_SUBST(MOZ_MOTIF_CFLAGS)
 AC_SUBST(MOZ_MOTIF_LDFLAGS)
 AC_SUBST(MOZ_XLIB_CFLAGS)
@@ -1845,7 +1867,8 @@ AC_SUBST(XLIBS)
 AC_SUBST(MOC)
 
 if test "$MOZ_ENABLE_GTK" || test "$MOZ_ENABLE_QT" \
-|| test "$MOZ_ENABLE_XLIB" || test "$MOZ_ENABLE_MOTIF"
+|| test "$MOZ_ENABLE_XLIB" || test "$MOZ_ENABLE_MOTIF" \
+|| test "$MOZ_ENABLE_GTK2"
 then
 AC_DEFINE(MOZ_X11)
 fi
diff --git a/mozilla/gfx/src/Makefile.in b/mozilla/gfx/src/Makefile.in
index 26f33ffad97..d762192c005 100644
--- a/mozilla/gfx/src/Makefile.in
+++ b/mozilla/gfx/src/Makefile.in
@@ -50,6 +50,9 @@ else
 ifdef MOZ_ENABLE_GTK
 DIRS		+= gtk
 endif
+ifdef MOZ_ENABLE_GTK2
+DIRS		+= gtk2
+endif
 ifdef MOZ_ENABLE_MOTIF
 DIRS		+= motif
 endif
diff --git a/mozilla/widget/src/Makefile.in b/mozilla/widget/src/Makefile.in
index 7a3cd3fa04e..030a137b8a6 100644
--- a/mozilla/widget/src/Makefile.in
+++ b/mozilla/widget/src/Makefile.in
@@ -43,6 +43,10 @@ DIRS            += gtkxtbin
 DIRS		+= gtk
 endif
 
+ifdef MOZ_ENABLE_GTK2
+DIRS		+= gtk2
+endif
+
 ifdef MOZ_ENABLE_MOTIF
 DIRS		+= motif
 endif