diff --git a/project.properties b/project.properties
index 24ee10753..26e0d9eff 100644
--- a/project.properties
+++ b/project.properties
@@ -43,6 +43,7 @@ maven.changes.issue.template=http://issues.apache.org/bugzilla/show_bug.cgi?id=%
 maven.jar.override = on
 maven.jar.clover = 1.3.2
 maven.compile.target=1.3
+maven.compile.source=1.3
 
 maven.announcement.file=${basedir}/RELEASE-NOTES.txt
 maven.announcement.stylesheet.path=${basedir}/release-notes.jsl