Fatal error: Cannot redeclare class

Hello,

I'm trying to modify my own template, until now I have only changed the header. But I'm getting an error when I'm trying to access the information sites.

Links:

http://www.iclooly.net/store/index.php? ... ommon/home

http://www.iclooly.net/store/index.php? ... duct_id=50

Help would be really appreciated!
Thanks