When I am attempting to access an url that's very lengthy (eg. http://my-domain.com/abc/here-is-a-very-long-filename-about-400-characters) I recieve Bad Request (Invalid URL) from IIS and 403 file not available on apache.
This issue continues to be reported like a bug at apache's bug confirming but no concrete solutions where given.
It appears that both servers (IIS and apache) in some way see if "here-is-a-very-lengthy-filename-about-400-figures" is really a file around the disk even when it's being mod_rewrited by .htaccess after which happens when it throws a mistake.
I really hope I made myself obvious enough to have your call answered, otherwise please request for additional particulars.
Ignore any misspelling!