Author: Daniel Baumann <daniel.baumann@progress-technologies.net>
Description: Avoid overwriting build-environment.

diff -Naurp clzip.orig/configure clzip/configure
--- clzip.orig/configure	2012-06-27 16:02:18.168455662 +0200
+++ clzip/configure	2012-06-29 04:37:06.563567740 +0200
@@ -23,9 +23,9 @@ datarootdir='$(prefix)/share'
 infodir='$(datarootdir)/info'
 mandir='$(datarootdir)/man'
 CC=
-CPPFLAGS=
-CFLAGS='-Wall -W -O2'
-LDFLAGS=
+#CPPFLAGS=
+#CFLAGS='-Wall -W -O2'
+#LDFLAGS=
 
 # Loop over all args
 while [ -n "$1" ] ; do