form_validation doesn't accept strings with http://

[eluser]Unknown[/eluser]
Hi I need help. My form_validation doesn't accept string containing http:// I have tested the form using www.mywebsite.com and it works, but as soon as I add http://mywebsite.com the form_validation->run always returns false.

One weird thing is that it does work on my localhost, but not on my webserver.

Any ideas?? Would really appreciate the help.