diff --git a/prebuild.xml b/prebuild.xml
index ca27e2cfed..82c4dc9e69 100644
--- a/prebuild.xml
+++ b/prebuild.xml
@@ -730,6 +730,7 @@
 
       <ReferencePath>../../../bin/</ReferencePath>
       <Reference name="System"/>
+      <Reference name="System.Core"/>
       <Reference name="System.Xml"/>
       <Reference name="System.Web"/>
       <Reference name="OpenMetaverseTypes" path="../../../bin/"/>