Server Side Includes with client folders

Hello, I am rather new to Server Side Includes, and the Module in apache is active. They work when I put a .shtml file in the main Documents folder of the WebServer folder in Library, everything works fine. However, in my client folders: www.mysite.com/~user/file.shtml the SSI's don't get processed, they don't work. Anyone know why this might be? Thanks in advance. -- vlad