Hi,
thanks for the comments/tips upon a solution for a "One-Click Unsubscribe".
For anyone interested, here is a short summary of what we did:
everything about mailman is great - everything but the frontends :-)
http://www.orenet.co.uk/opensource/MailmanMysql/
CMS" (www.papaya-cms.com - note: the page is only available in german until spring '06)
subscriptions und unsubscriptions and keeps track of all relevant dates, due to requirements of the german laws
papaya syncs this database with the mailman maysql-database
and everything is fine ;-)
Again, thanks for any comments upon our problem - and thanks to the developers for mailman and the MySQL MemberAdaptor...
Best regards!
André