Split testing software and nested php

Lots of these split testing software programs seem to use php/mysql. Problem I've got is that I want to test two versions of a page that has lots of php within it. So if I place their php tag to flipflop the two different pages, the code would break because there would be nested php.

Any ideas of a solution?

Thanks,

Jon

 

If the existing code has

<?php 
// Add your code below without <?php ?>
?>

Code (markup):

I am curious to which tool your using. I need to do some as well.
Can you PM me a link to what your using ?

 

I wanted to use split testing accelerator but I believe that does not allow this nesting of php. So currently I'm not using a tool.