HELP, Postgres stops accepting connections from Unix socket

I earlier thought that is was that it stopped accepting connection from
localhost but realized that it is not true, it's the ONLY the Unix
socket connection that stopped working. The socket is set correctly
('5432') and it does work for a day but always the next day I need to
restart the postmaster in order to get postgres accepting connections
from Unix socket. WHY ?????
Once again ANY help would be greatly appreaciated by this newbie.

Postgres 6.5.3 is running on 2.2.14 kernel linux pc.

-michael (A)