What Would Make Sudo Always Let one Execute a Command?

[Martin G. McCormick]

Sudo behaves as if the default timeout in sudoers was set to -1.
Out of 5 FreeBSD9 systems, this one system exhibits this
behavior while all the others time out like they should. Setting
the value to 0 should cause one to always have to enter a
password, but not on this system.
	Has anyone ever seen this before? The sudoers file is a
copy of the same sudoers file we use on the other machines. I
have also tried sudo from a few other user ID's on the system
and see the same behavior.
Thank you.

Martin McCormick