connection limit exceeded

Hi Everybody,

On my postgres 8.1.1, I get a response
psql: FATAL: connection limit exceeded for non-superusers

A few questions come to mind...

1) Is this to do with max_connections setting in the postgres
configuration file? (my setting is 100 (I think this is the
default).)
2) how would I look at the "open/used" connections?
3) should I try restarting postgres without changing the setting?
4) what repercussion would there be if I increase this number to,
say, 200? (and would that be a good idea?)
5) finally, what's the best fix? (Do I need to go to pgpool?)

Many thanks in advance.

Regards,

Tena Sakai
tsakai(at)gallo(dot)ucsf(dot)edu