"Unresolved Import" in php4isapi.dll with PHP 4.2.1 with IIS5.1 on WinXP/IE6

Hi ! I found so may hints about this problem but none with a solution. I can't configure IIS5.1 on my german Windows XP Prof. with IE6 to run PHP 4.2.1, neither with php4isapi.dll nor with just the CGI. In every case the OK-Button won't get active in the configuration window of the IIS manager (as explained in install.txt). I can run php.exe from a DOS command line, and it will produce the correct output (e.g. php phpinfo.php >phpinfo.html or just a HelloWorld.php). I had the same problem on my older PIII-notebook with Win2k/SP2. When I deinstalled IE6 and installed IE5.5 everything worked fine on this machine. But with my new P4-notebook and WinXP Prof. I don't want to fiddle around with the configuration by "downgrading" to IE5.5 The follwing error is reported by Dependency Walker on php4isapi.dll: Unresolved import... in MPR.DLL: WNetRestoreConnectionA. As Windows NT/2000/XP are "UNICODE"-enabled, I guess that none of the PHP4 modules (or whoever makes this reference) should reference any of the ...A-functions and should always use ...W-functions. But I guess that my configuration with PHP on WinXP/IIS5.1/IE6 should be quite common, so I hope that anybody out there had the same problem and found a solution. TIA, Stefan P.S.: Please also email any answers to me...