Question : force signature in outlook

Dear All,

I have Exchange 2010 installed on my environment. I'm looking to force a signature template in Outlook 2007 and Outlook 2010 for all mailboxes and block the change by user. How I can do that?

Is it doable by exchange or by GPO?

Thanks

Answer : force signature in outlook

Exchange 2010 seems to support this feature using Transport Rules.  Just a couple of quick "Hey, look at this cool new feature!" links I stumbled across:
http://www.networkworld.com/community/blog/standardized-signatures-exchange-server-2010-?source=nww_rss
http://csolarz.spaces.live.com/blog/cns!DBA51C9F747ECD38!531.entry?wa=wsignin1.0&sa=10332669
http://markswinkels.nl/2010/01/18/how-to-exchange-2010-e-mail-signature-based-on-active-directory-information/