--- Makefile.orig	2013-03-17 11:38:57.213776000 +0000
+++ Makefile
@@ -13,7 +13,7 @@ RFLAGS     = -DRELEASE=$(COV_RELEASE) -D
 ## greatly speeding scans of unfinished sequence
 
 ## where Perl v.5 (or greater) is installed
-PERLDIR = /usr/bin
+PERLDIR = $(PREFIX)/bin
 
 ## what you call the Perl v.5 executable on your system
 ## (this could be 'perl5' or otherwise on some systems)