I've install PHP4, horde, IMP in Debian. When I access the mailbox by 127.0.0.1/horde, I get the login interface, I can log in, and see the information about e-mails:from where, who and the subject, and the size, but when I click the subject ,or date, or compose, or any other href, I can not go ahead, I only get the login infterface again. Why?