yes, I already did this before posting here. The missing http header does not come from the socket stream in AbtWsiConnectionTcp>>receiveRequest: . In 7.5 the socket stream answers the missing http header REMOTE_USER.
This means it the header is not removed by Smalltalk but it is not delivered trough the ISAPCI/CGI DLL oder .exe.
The result of the missing http header is that no customer of our application can use the “single sign on” via Microsoft NTLM after migration to the VA 8 version of our application