CMS Made Simple Forums

hey,

is it possible to add my own use defined module for example my own reservation module built with php onto the cmsms?

Sure you can. CMS Made Simple has so called "User Defined Tags" (UDT's), pieces of PHP code that can be edited from the admin and included in your pages.
If that is not enough you can create your own module (and register it in the forge if you want).

Regards,
D