Our company (ppedv AG) is Microsoft gold partner and this includes 5 free support calls. This week we hade a problem with VPN access from outside through ISA 2000. Both of our admins were not in the office. Normaly i am quite familiar with RRAS and ISA to configure that, but in this case after 3 hours trying i gave up and opend on of our support calls.
Friendly, competent and the will to help.. great, thanks for that.
After 3 hours phone call and remote assistance the MS guy figured out that SP1 of W2003 have buggy nat.sys. There exist a patch and bumm.. works again.
Thanks to Volkan Yilmaz from Microsoft Germany!