Thanks Darren,
I believe I am doing the reverse. current_timestamp is local to where the server is based, or what the sysadmin has set the server's timestamp to be.
I have a process that performs work for the user based on the user's local time, taking daylight savings time into account.
So it appears I have to cons up a string representing the user local time and then tack on a string representing the gmt offset to convert it to a server based time.
An additional hardship is that pg doesn't implement the full set of timezones around the world, It implements some of them. Jon Griffin surged ahead and found rules for 496 different time zones some for instance with 15 minute offsets.
So it seems like I can't really use much of pg 7.2.4's timezone support (which isn't much and hard to figure out anyway.)