diff -Naur ../ant.orig ../ant
--- ../ant.orig	2011-12-21 00:30:53.931359653 +0200
+++ ../ant	2011-12-21 00:32:03.624364254 +0200
@@ -87,7 +87,9 @@
   exit 1
 fi
 
-ANT_HOME="${EPREFIX}"/usr/share/ant-core
+if [[ -z "${ANT_HOME}" || ! -d "${ANT_HOME}" ]] ; then
+  ANT_HOME="${EPREFIX}"/usr/share/ant-core
+fi
 
 
 # set ANT_LIB location