I think this was an error. We are still 1.5 compatible? When merging lucene + solr this is a bad idea.

git-svn-id: https://svn.apache.org/repos/asf/lucene/solr/branches/solr@923635 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/common-build.xml b/common-build.xml
index c57102c..0ee504d 100644
--- a/common-build.xml
+++ b/common-build.xml
@@ -52,7 +52,7 @@
   <property name="svnversion.exe" value="svnversion" />
 
   <!-- Java Version we are compatible with -->
-  <property name="java.compat.version" value="1.6" />
+  <property name="java.compat.version" value="1.5" />
 
   <!-- Solr Implementation Version -->
   <!--