--- Makefile.BAK	Sat Feb 27 21:25:27 1999
+++ Makefile	Sat Feb 27 21:25:32 1999
@@ -3,7 +3,7 @@
 # Prefix for installation. /usr/local is probably a reasonable choice
 # on most systems; you may prefer to make this your home directory if
 # you do not have root access on the system you're using.
-PREFIX=/usr/local
+PREFIX?=/usr/local
 
 #---
 
