Dear Rob! Dear Eric!
That's the first time I ever heard about this error. Very strange.
Rob: The first time (your posting from 14:57) you looked into the wrong error_log. You looked into the error_log from a Apache shipped with RedHat. The error_log from XAMPP's Apache is located under /opt/lampp/logs/. Just to explain this little matter.
Could you both please simply call this both commands (one after the other):
/opt/lampp/bin/php-4.3.11 -v
/opt/lampp/bin/php-5.0.4 -v
What output do you get?
As far I can see from here PHP is no longer running on your systems. And because PHP is included into Apache the Apache also didn't start. But first I want to find out if PHP5 or PHP4 or both are affected.
Best regards
Oswald