Ok here's the analysis;
Without applying your changes the following work;
Twitter, +1, Linkedin, Delicious (although instead of a new window delicious replaces my page), Digg.
Without applying your changes the following do not work;
Facebook, Reddit, Google Buzz.
After applying your changes they all work (delicious now pops up instead of replacing page) and Google Buzz went from not working to displaying a pop up with a 404 error.
I'm happy as it all works but I still question why the php code doesn't work the same for all of them as shown above. And could you help me fix google buzz?
Thanks for all your help
PS
I'm on Version 2.0.0
PPS
Maybe there is a bug that causes incomplete php code to be generated when the target page is not in the root folder.
index.php - correct php code
about.php - correct php code
witty.php - incorrect php code
Just a thought...