Varying messages to different signatories

Is there a way to send different messages to each sigantory assigned to an agreement?

Situation: We have information required by internal signatories that should not be seen by external signatories. I obviously cannot include the information on the main document, but rather hoped to include the information in a message sent only to the internal signatories. However I'd want to send a different message to external signatories. Is this a possibility?