diff -Naur mono-9999.bak/mono/mcs/tools/gacutil/driver.cs mono-9999/mono/mcs/tools/gacutil/driver.cs
--- mono-9999.bak/mono/mcs/tools/gacutil/driver.cs	2010-07-03 04:58:15.000000000 +1200
+++ mono-9999/mono/mcs/tools/gacutil/driver.cs	2010-07-03 05:13:01.000000000 +1200
@@ -808,7 +808,7 @@
 		private static string EnsureLib (string dir)
 		{
 			DirectoryInfo d = new DirectoryInfo (dir);
-			if (d.Name == "lib")
+			if (d.Name == "lib" || d.Name == "@MONOLIBDIR@")
 				return dir;
 			return Path.Combine (dir, "lib");
 		}
diff -Naur mono-9999.bak/mono/mono/metadata/assembly.c mono-9999/mono/mono/metadata/assembly.c
--- mono-9999.bak/mono/mono/metadata/assembly.c	2010-07-03 04:58:14.000000000 +1200
+++ mono-9999/mono/mono/metadata/assembly.c	2010-07-03 05:11:47.000000000 +1200
@@ -542,7 +542,7 @@
 	}
 
 	config = g_build_filename (base, "etc", NULL);
-	lib = g_build_filename (base, "lib", NULL);
+	lib = g_build_filename (base, "@MONOLIBDIR@", NULL);
 	mono = g_build_filename (lib, "mono/1.0", NULL);
 	if (stat (mono, &buf) == -1)
 		fallback ();
@@ -595,7 +595,7 @@
 
 	bindir = g_path_get_dirname (name);
 	installdir = g_path_get_dirname (bindir);
-	root = g_build_path (G_DIR_SEPARATOR_S, installdir, "lib", NULL);
+	root = g_build_path (G_DIR_SEPARATOR_S, installdir, "@MONOLIBDIR@", NULL);
 
 	config = g_build_filename (root, "..", "etc", NULL);
 #ifdef HOST_WIN32
@@ -2066,7 +2066,7 @@
 	if (extra_gac_paths) {
 		paths = extra_gac_paths;
 		while (!res && *paths) {
-			gacpath = g_build_path (G_DIR_SEPARATOR_S, *paths, "lib", "mono", "gac", aname->name, NULL);
+			gacpath = g_build_path (G_DIR_SEPARATOR_S, *paths, "@MONOLIBDIR@", "mono", "gac", aname->name, NULL);
 			res = probe_for_partial_name (gacpath, fullname, aname, status);
 			g_free (gacpath);
 			paths++;
@@ -2117,7 +2117,7 @@
 		if (*gp != G_DIR_SEPARATOR)
 			continue;
 		gp++;
-		if (strncmp (gp, "lib", 3))
+		if (strncmp (gp, "@MONOLIBDIR@", 3))
 			continue;
 		gp += 3;
 		if (*gp != G_DIR_SEPARATOR)
@@ -2196,7 +2196,7 @@
 		paths = extra_gac_paths;
 		while (!image && *paths) {
 			fullpath = g_build_path (G_DIR_SEPARATOR_S, *paths,
-					"lib", "mono", "gac", subpath, NULL);
+					"@MONOLIBDIR@", "mono", "gac", subpath, NULL);
 			image = mono_image_open (fullpath, NULL);
 			g_free (fullpath);
 			paths++;
@@ -2488,7 +2488,7 @@
 	if (extra_gac_paths) {
 		paths = extra_gac_paths;
 		while (!result && *paths) {
-			fullpath = g_build_path (G_DIR_SEPARATOR_S, *paths, "lib", "mono", "gac", subpath, NULL);
+			fullpath = g_build_path (G_DIR_SEPARATOR_S, *paths, "@MONOLIBDIR@", "mono", "gac", subpath, NULL);
 			result = mono_assembly_open_full (fullpath, status, refonly);
 			g_free (fullpath);
 			paths++;