Getting 404 when requesting url as https

Hi,

I am facing a weird issue with my wordpress blog. The site working fine if I request urls as:
https://subdomain.domain.com/permalink-to-my-page
But if I request the same url as:
https://subdomain.domain.com/permalink-to-my-page
it is ending with a 404 error.

My server is a godaddy VPS i believe running Operating system CentOS Linux 5.6

I have a SSL cert. installed.

Please help.

Thank you.