Apache, PHP and Windows XP

I had this working last week and previously on other machines... and I'm about to remove & re-install for a second time since!

I've got Apache 1.3 installed, PHP 4.3.7 (and MySQL as it happens...but that's not part of the problem) on a Windows XP machine.  It's just my workstation & I use it for testing web sites before making them live.

Every time I go to use a php page, I get an error in the main Apache error log:

[Fri Mar 18 16:36:22 2005] [warn] mod_mime: analyze_ct: cannot get media type from 'x-mapp-php4'

... and the php page does nothing.

I have a test page (test.php) with simply:

<?php
  phpinfo();
?>

... and I get a blank page back in the browser and the entry in the error log.  I have a shed-load of other php pages that perform the same, but figured I'd point out the simplest here.

Pertinent entries in the httpd.conf:

---------------------
LoadModule php4_module "C:/Program Files/php/sapi/php4apache.dll"
AddModule mod_php4.c

<IfModule mod_dir.c>
    DirectoryIndex index.php index.html
</IfModule>

<IfModule mod_mime.c>
    ....
    AddType application/x-httpd-php      .php
    ....
</IfModule>
---------------------

As you can see PHP is set up in the C:\Program Files\php directory & the cli version works a treat.  The php.ini is in the %SYSTEMROOT% and the php4ts.dll is in the %SYSTEMROOT%\SYSTEM32.

I've tried adding the following line to the mod_mime.c section of httpd.conf also, but with no change to the symptoms after a restart of Apache (killed the logs to be sure!):

    AddType application/x-mapp-php4      .php

Any ideas why it's all not gelling together?  Unless there's a snappy answerer (I'm just about to go home for the weekend), I won't be looking at the matter until Monday (GMT) morning.