problems with includes after upgrade from 5.2.1 to 5.2.11

Hi, I just upgraded php and am using it with IIS / FastCgi. Now all my code 'includes' and 'requires' are failing as they don't have drive letters :( This does not see to happen if you run from the command line. My php files are all stored on drive e: Previously all my code just referenced full paths like /mysite/includes/test.php Now I find this does not work unless I use e:/mysite/includes/test.php Any way to fix this without having to change 1000's of lines of code!? Thanks, Paul