This patches let you disable Tk even if you have it installed and
makes sure the TCL-library is added as a dependency for libpgtcl.
--- interfaces/libpgtcl/Makefile.in	Tue Mar  7 20:58:36 2000
+++ interfaces/libpgtcl/Makefile.in	Wed Sep 20 08:57:28 2000
@@ -29,3 +29,3 @@
 
-SHLIB_LINK+= $(LIBPQ)
+SHLIB_LINK+= $(LIBPQ) @TCL_LIB_SPEC@