diff --git a/mozilla/mailnews/db/msgdb/build/nsMsgDBFactory.cpp b/mozilla/mailnews/db/msgdb/build/nsMsgDBFactory.cpp
index 3bfbada1a37..aef5bd2c91c 100644
--- a/mozilla/mailnews/db/msgdb/build/nsMsgDBFactory.cpp
+++ b/mozilla/mailnews/db/msgdb/build/nsMsgDBFactory.cpp
@@ -85,6 +85,7 @@ nsresult nsMsgDBModule::Initialize()
 // Shutdown this module, releasing all of the module resources
 void nsMsgDBModule::Shutdown()
 {
+	nsMsgDatabase::CleanupCache();
     // Release the factory objects
     mMailDBFactory = null_nsCOMPtr();
     mNewsDBFactory = null_nsCOMPtr();