Creating Threads in Visual C++ DLL used by Delphi Project

I have a problem with creating threads in a Visual C++ 4.0 DLL when it is used
by a delphi 2.0 program. I get a strange "assertion failure in line 71 of
thrdcore.cpp" whenever a thread is created (with AfxBeginThread) in a function
of the DLL called by delphi. When i use the same DLL from a C++ program there
seems to be no problem. Help would be appreciated since i am not really a
delphi expert :)