Force all Outlook clients to append a disclaimer to all out-bound mail?

Hi - do you have Exchange?  

yes, but i don't want to use any disclaimer software until in migrate to exchange 2003 server (which would take around 3 months)
presently my mailboxes are on exchange 5.5
i am looking for some client side tool/tweek

Sorry - hit send too quickly.  

If you are using Outlook, you could have the users create email Signatures that have the outgoing text that you are requiring.  

If you are running Exchange, then, there's an automated way to handle this issue.

is there a way to append a small disclaimer to the signature of all users?

Yes, there are tools listed in this site that appear to have that functionality.

http://www.slipstick.com/addins/sig.htm

PS - you may want to consider migrating to Exchange 2007, rather than the 2003 version.  After your 2003 effort, you'll still be a step behind.

Hi again - I just saw this product mentioned in a separate post, and also has the functionality that you're looking for.

http://www.symprex.com/products/msm/

is there any GPO that can be implemented so that it appends a footer to the signature of all Outlook users?

thanks. will try the solutions that you provided.

Great.  Thanks for the points/grade.