CMS Made Simple Forums

Hi,

At the moment Im trying to install the latest cmsms.
But after installation step 4,  I get this error:

Fatal error: Class pear_extender: Cannot inherit from undefined class mysql_transaction_adoconnection in /homepages/6/d198991802/htdocs/Zellmann1/lib/adodb_lite/generic_modules/pear_module.inc(5) : eval()'d code on line 1

I have no idea what it means and I couldn't find any help on the net yet 

Im using PHP 4.0

thanks!