dump mime attch. to disk

Hi,

I'd like to exctract incoming attachments (like zip files) to a certain
directory automagically by procmail, how would I do that ?

thx for ur help
bye
-- 
Christophe Zwecker                email: doc(_at_)rrz(_dot_)uni-hamburg(_dot_)de
Hamburg, Germany                    fax: 49 40 22715433