--- Makefile.inc.orig	2010-08-30 23:27:33.000000000 +0100
+++ Makefile.inc	2010-08-30 23:27:53.000000000 +0100
@@ -26,7 +26,7 @@
 DEBUG=-g $(PDEBUG)
 OPT=
 
-REXX_INCLUDE=$(HOME)/regina
+REXX_INCLUDE=$(PREFIX)/include
 CFLAGS=$(DEBUG) $(OPT) $(PCFLAGS) $(PCDEFS) -I $(REXX_INCLUDE)
 LDFLAGS=$(PLDFLAGS)
 LIBS=$(PLIBS)