diff --git a/build.sh b/build.sh
index 722224a..0c551e4 100755
--- a/build.sh
+++ b/build.sh
@@ -38,7 +38,7 @@
 ANT_ARGS="-Dant.regexp.regexpimpl=org.apache.tools.ant.util.regexp.JakartaOroRegexp $ANT_ARGS"
 
 # raise heap/stack size...
-ANT_OPTS="-Xss512k -Xmx128m -mx128m"
+ANT_OPTS="-Xss1024k -Xmx256m -mx256m"
 
 # set classpath
 CLASSPATH=./lib