Internal Server Error

Give us your Gallery/webserver information to get a faster answer.
Get this information from the PHP diagnostic (in the configuration wizard).
Gallery URL (optional but very useful): www.prettyfly.co.za/gallery
Gallery version:v1.5.3
Apache version: Apache/1.3.26
PHP version (don't just say PHP 4, please):PHP v4.3.1
Graphics Toolkit: Image Magick
Operating system: OS X
Web browser/version (if applicable): Safari

After installing the script and loggin in, when i want to create a new album, or just want to view a album, i get the following error:
Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator,

and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Apache/1.3.26 Server at prettyfly.co.za Port 80

The peculiar thing is that, clicking on the album link, points my browser to www.mydomain.co.za/galler/album01, but my albums directory has been set to www.mydomain.co.za/gallery/albums.

If i point my browser to www.mydomain.co.za/gallery/albums/album01, i get the following error:
Forbidden

You don't have permission to access /gallery/albums/album01/ on this server.

Apache/1.3.26 Server at prettyfly.co.za Port 80

Please help! I think the software is awesome from what i see, but it sux that i can't use it...