--- xgui/Makefile.orig	Sun Sep 24 23:32:13 2000
+++ xgui/Makefile	Sun Sep 24 23:32:30 2000
@@ -17,7 +17,7 @@
 # Include machine/platform specific information into the build
 include ../machdef.mk
 
-CFLAGS=-I. $(TCL_INCLUDE) $(X_INCLUDE) $(OPTIONS) $(MACHINESPEC) -DPREFIX=\"$(PREFIX)\"
+CFLAGS+=-I. $(TCL_INCLUDE) $(TK_INCLUDE) $(X_INCLUDE) $(OPTIONS) $(MACHINESPEC) -DPREFIX=\"$(PREFIX)\"
 
 OBJECTS = \
 	globals.o \