Root password problem

[rzbz13%punkass.com@localhost]

I can no longer login to my root account. I have not
forgotten my password, it just won't work. When I try
to login I get the message -

Login incorrect or refused on this terminal.

Then the terminal gives this message-

login: Login timed out after 300 seconds

If I boot up with boot -s to single user mode and try to
change the password with the command passwd, it goes through

Changing password for root.
New Password:
Retype New Password:
The password file is busy, waiting...
The password file is still busy, try again later.
Unable to change auth token: error in service module

I enter the new password at both prompts then the rest comes up
immediately. Later never seems to come. If I try to use vi to
open /etc/master.passwd in single user mode I get

WARNING: TERM enviroment variable not set.
ex/vi: Error: /var/tmp/vi.recover: Read-only file system
ex/vi: Modifications not recoverable if the session fails
ex/vi: Error: /etc/master.passwd: Read-only file system
ex/vi: Error: Unable to create temporary file: Read-only file system

Can someone tell me what's going on, and what I can do to fix it.
I am certainly not the most skilled NetBSD user. If I need to give
more info, let me know what I should give. I'm using i386 ver.4.0.
Thank You, Rob

--
Doubt is not a pleasant condition, but certainty is absurd.
                -- Voltaire