Indeed it is possible to have your mail forwarded to your new address.... I did it a couple of times and it worked just fine. However, it is not for free....

Visit the Swiss Post web site for more info:
http://www.post.ch/fr/index_pm/pm_pr...zugservice.htm
(only available in FR, IT, DE).

All you have to do is go to the Post, show your ID, fill some papers and they do it on the fly. You can also do it online

Hope this helps!