Running Apache 2.0.55 or 2.2.0 under Windows with PHP 4.4.2 (the latest 4 version), I get a crash when loading a simple PHP file containing (example file):
<?php
@readfile('http://aDomain/main.php?g2_view=imageblock.External&g2_blocks=randomImage&g2_show=title');
?>

Calling that same URL directly from a browser works fine.

Testing the same file under the latest CVS version of PHP4 (4.4.3?), it works fine. So it must be a bug that was corrected.
It appears to be a bug specific to 4.4.2.
My problem here is that eAccelerator does not work on PHP4 past 4.4.2.

Update: This bug does not exist on 4.3.11
Which is, by the way, a lot faster then PHP4.4.X or PHP5.1.X series...