CB Newbie - Email User Question

I am very new to CB - so this may be a dumb question - but here goes.

I am interested in tracking a date/time stamp for when an email message was last sent to a user.

I can see that the jos_comprofiler.message_last_sent element seems to track the last time that a user sent an outbound message. Is there something similar that will show when a user was last the receipient of an email message?

Thanks,
Kevin

BUMP - how hard would it be to change the target of the timestamp from the current implementation of the outbound message sender to the timestamp of the inbound message receiver? Thoughts?