Mail Disclaimer strange error on Exchange 2010

Hi all;

Signatures are not working for end users, and I can see the following error in Event Viewer on both exchange servers "Exchage 2010 update rollup 6".

 Creating Transport Routing Agent

System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.

at System.ThrowHelper.ThrowKeyNotFoundException()

at System.Collections.Generic.Dictionary`2.get_Item(TKey key)

at Exclaimer.Connectors.MailRules.Transport.Factory.CreateAgent(SmtpServer server)

I can see that the related TransportAgent is enabled...

Please help.

Regards.