Fix building the Mac version with GUI.
diff --git a/src/Makefile b/src/Makefile
index 00306b9..5719b3c 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -357,6 +357,9 @@
 #CONF_OPT_GUI = --enable-gui=athena
 #CONF_OPT_GUI = --enable-gui=nextaw
 
+# Carbon GUI for Mac OS X
+#CONF_OPT_GUI = --enable-gui=carbon
+
 # DARWIN - detecting Mac OS X
 # Uncomment this line when you want to compile a Unix version of Vim on
 # Darwin.  None of the Mac specific options or files will be used.