I've found what seems like a bizarre problem with IIS 6.0 and .NET 3.5. I always use the tilde for all URLs (eg: ~/mypage.aspx) so if I go to mydomain.com/mypage.aspx, everything works fine. If, however, I add a trailing slash and go to mydomain.com/mypage.aspx/, all links on the page which use the tilde get rendered as mydomain.com/mypage.aspx/otherpage.aspx instead of mydomain.com/otherpage.aspx.
This happens with all controls.
Has anyone had this issue before?