[TYPO3-dev] double login

[Steffen Kamper]

Hi,

i have a special usecase on a site (FE).

There is a normal login via doccheck (it's an extension and a special 
service for medicals)
They are logged in as a dummy user in FE

There are special services (pages) that are restricted to a special 
usergroup, they can register for it when they are logged in.
When they want access the special area they have to change the fe user

So i made a login with a html element, which works.

But after navigating to other pages TYPO3 seems to forget about that user, 
all is mixed

* CEs should be hidden for logged in are shown, also the CE's "show after 
login"
* seems that usersessions are mixed

What can i do, how can  i make a user switch without log out in a clean way?

vg Steffen