[otrs] Handling internal responses

We're looking at using OTRS to handle our support call tracking. It looks great so far, and is much faster than RT3 ;-) So what normally happens here is that someone emails support@isode.com, and I can set up OTRS to spot these messages, create a call and send an auto response. Now when someone internal responds to a call, they email the customer and 'cc' support@isode.com. Is there any way for OTRS to detect those responses and to set the call to an appropriate state? Folks here hate using a web interface to send email, so having a way to update the call without using the web interface would be greatly appreciated :-) Cheers, Chris