I just spent about an hour trying to figure this out, but when you have a php application that requires call time pass reference to be enabled, you can set in the .htaccess file.  The trick on some systems is that it must be set to “1″ and not “on” as is indicated on the PHP support forums. here’s the code:

php_flag allow_call_time_pass_reference 1

Whether or not you need to use “1″ or “on” seems to depend on the install and whether you’re using PHP version 4 or 5.