I was emerging gnome at home, and sshed into the computer from school. This afternoon I went home and rebooted the machine. It was still in text mode, no GUI what so ever, however, I wasn't able to login. after I typed in my username, the system would wait for a few seconds and then goes back to the username prompt again, without ever asking me for password.

now i am back in school, I could ssh into the machine without any problem. Does anyone know what the problem might be? How do I solve it?

[SOLUTION]

i must have unmerged pam-login at some point without updating shadow. the problem went away after I emerge --update shadow and util-linux

anyone please?

If you can ssh into the system,
go check the /etc/pam.d/ directory or /etc/pam.conf file (dep on system)
and look at login section and system-auth section, maybe you
got a pam-deny module loaded where an authenticatin module must be.