>- first hit creates a MMF COM application object in the first apartment, which saves it's reference into goApp
>- second hit from another user (some milliseconds later) creates another instance of the same MMF COM application object in the second apartment, which saves it's reference into goApp too
>- that means, the first reference is overwritten, and some code in the first instance may use the second instances goApp!
>
>Is my error the usage of a cApp.vcx::cApplicationCom derived class in ASP.NET environment - or where I'm wrong?
>

Hmm...I looked at the code in CApplicationCOM class and it looks like you could easily fix your problem just by changing the code in Init() slightly. Currently there isn't any check to see if goApp exists:

PUBLIC goApp

goApp = This

You might be able to just change this to:

IF VARTYPE(goApp) <> "O" 
   PUBLIC goApp
   
   goApp = This
ENDIF