connection time-outs

hello,

maybe this has been asked a thousand times, but as the archive seem not to
respond to any search, here is my question:

Is there a way to parametrize the connection time-out, when starting the
postmaster, or something like that? The connection to postgres are timed
out after some 3 or 4 minutes. I am running postgres 7.0.1 on a Linux Rehat
6.1, and accessing it using JDBC using the jdbc7.0-1.2.jar.

thank you very much,

Stan.