Yes, WebSessions are still valid (see
http://translate.google.com/translat...F8&sl=de&tl=en).
The required German Vodafone prepaid SIM is called "CallYa" and not "CallNow", as the cited page says. "CallNow" is the designation of the top-up vouchers.
You can get a CallYa SIM for absolutely free at
http://www.gratis-callyakarte.de/ (shipping only within Germany) or ask me and I'll send you a spare CallYa SIM also abroad.