diff --git a/prebuild.xml b/prebuild.xml
index ac4400dc68..8761a150a5 100644
--- a/prebuild.xml
+++ b/prebuild.xml
@@ -2900,6 +2900,7 @@
 
       <ReferencePath>../../../bin/</ReferencePath>
       <Reference name="System"/>
+      <Reference name="System.Xml"/>
       <Reference name="Nini.dll"/>
       <Reference name="log4net.dll"/>