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--- a/Allura/allura/lib/exceptions.py
+++ b/Allura/allura/lib/exceptions.py
@@ -2,3 +2,5 @@
 class ProjectConflict(ForgeError): pass
 class ToolError(ForgeError): pass
 class NoSuchProjectError(ForgeError): pass
+class MailError(ForgeError): pass
+class AddressException(MailError): pass