Taking over PHP environment?

My webserver's admin has reported to me that he has a search.cgi which
is setup to run as PHP, but, under certain [presently unknown]
conditions, mod_ruby "takes over" and executes the script as Ruby, which
of course borks everything to heck, because it is not Ruby code, it's
PHP.  Now, this is extremely strange behaviour, to say the least.  :)
Any clues as to why this would occur?

He has said that if this doesn't get fixed, he is going to take mod_ruby
off, and I will be forced to pander around in something like PHP.  :(
Hopefully that won't have to happen.

Alex