Mod_perl conflict with PHP on HTTP_REFERER variable

Hi.

I'm using Apache 1.3.33 / PHP 5.0.4 / Perl 5.8.7 / Mod_perl 1.29 on linux
box.

And one of virtualhost using Perl::Run and the others using PHP only.

In the site using php, The value of environment variables like $HTTP_REFERER
is empty.

If somebody is suffering for same reason. reply please.

thanks