I can verify this. Same thing happens here too. I had to redirect login_form to :8080 before, since I could not login to CMF otherwise, using VHM. I changed auth_cookie from __ac to __ac_, and now I can login through VHM... Bug... I'll put it in the Collector. (I'm using a week old cvs snapshot of Zope-2_5-branch and CMF1.2) /Magnus
I started debugging Zope. I found that the various methods in CookieCrumbler are called and should normally set a cookie for auth_cookie.
However, under VHM operation, this does not happen when auth_cookie == '__ac'
I changed the name of the authentication cookie to __ac_erp5 in the CMF (www.erp5.org is the site I am working on).
Everything works fine now.
I have absolutely no idea what it can mean.
As a reminder, I had no problems for 6 months and suddenly, after a small upgrade, all this strange behaviour started.