If you were a fan of the ‘bounce’ feature in the previous version of Mail, you may be disappointed that it has been removed in Mail Version 5.x

If you want the feature badly enough, you can either

1. Use this add-on for Mail.app in Lion
Restore Bounce Mail Button To Lion’s Mail

or

2. Use Mozilla’s Thunderbird.app instead of Mail, and get the ‘Mail Redirect‘ add on.