EV7 archiving on a front-end OWA server

I have a customer who is requesting that I install the EV7 archiving server on their front-end OWA server (Exchange 2003).  Their thinking is that because OWA is used primarily during business hours, and archiving runs mostly at night, they would be able to consolidate the roles onto one physical box.  Does anyone see a problem with this idea?  In theory, it should work, but I'm not sure of the nuances of the OWA extensions and how it would interact if it were on the same server.  Any input would be greatly appreciated...