demandimport problem in hgweb.cgi

[Terry]

We have a Windows2000 box with the following installed-
    Apache 2.2.6
    Python 2.4.4
    Mercurial 1.0.1 (using Mercurial-1.0.1-py2.4.exe)

I have set Mercurial up for Web access using hgweb.cgi, but when I tried it it fails as follows-

On the Webserver a 'python.exe - Application Error' Windows pop-up displaying-

X The instruction at "0x1e052305" referenced memory at "0x00000004". The memory could not be "read".

Clicking 'Cancel' to debug I get a Microsoft Visual C++ pop-up displaying-

i Unhandled exception in python.exe (PYTHON24.DLL): 0x00000005: Access Violation.

for line-

-> 1E052305   mov         eax,dword ptr [edi+4]

After I close the 'Application Error' pop-up I get the abort message at the client-

C:\Data\Hg\Demo03>hg clone "http://.../repos/hgweb.cgi"
destination directory: hgweb.cgi
abort: HTTP Error 500: Internal Server Error

The Apache error.log only displays- Premature end of script headers: hgweb.cgi

I have found that if I comment out the demandimport code line in hgweb.cgi it works perfectly.
Any ideas on what's causing this and what needs fixing?

Thank you
Terry