JDBC: can't connect in NT 4.0 SP 6 (JRE 1.2.2) as non-Administrator

I've encountered a subtle problem making a JDBC connection under NT 4.0 SP
6 running JRE 1.2.2. If I'm logged on as Administrator, the code works
fine. Under Linux, it works fine, same JDBC (6.5.3) classes. If I'm
logged into NT as a user, I can't connect to the Postgres server, and I get
this error on the client end:

The connection attempt failed because java.net.SocketException:
setsockopt<> TCP_NODELAY (code=10055)

On the Postgres end I just get:

pq_recvbuf: unexpected EOF on client connection

This is frustrating the heck out of me! What's REALLY annoying is that
it's not consistent - I CAN connect using another box (at home) under NT
4.0 SP 6 JRE 1.2.2!! Any guesses as to what's going on?

Sam Hokin ......................................... mailto:sam(at)ims(dot)net
Senior Developer ................... tel 608.277.0444 fax 608.277.1046
Internet Marketing Services ....................... http://www.ims.net