SharePoint Cannot Log in after making entry in hosts file

I'm building a MOSS 2007 site on Windows 2008 R2, 64 bit. Not wanting to use my machine name or IP in the URL, I made an entry in my hosts file:

127.0.0.1 mydev.com

I can surf to the URL, http://mydev.开发者_运维知识库com, but when I try to log in (Windows Authentication), I am denied. I am able to successfully log in if I take out the hosts file entry, and surf to http:// Do I need to edit something else for the authentication to work when I want to use a custom URL like mydev.com that is only mapped in the hosts file?

I needed to do this:

http://www.information-worker.nl/2009/06/23/disableloopbackcheck-on-windows-server-2008/

Do you have Kerberos authentication enabled? Then it is not so easy, since you try to access mydev.com, but your server cannot provide such authentication ticket. I'm not very common with Kerberos internals, but I have seen my servers act like this.