After much troubleshooting, I've come to the conclusion that the 6682 just simply does not support socket connections. This contradicts the claim in Q26 of this FAQ:,65...0,00.html#APIs

All MIDP 2.0 devices support socket connections.
I've been able to get both http and datagram connections to work on the 6682, but sockets always cause useless (meaning, uninformative) SecurityExceptions as explained here:

Unless I have to sign the midlet with a verisign certificate instead of a self-signed cert, the 6682 (and probably 6680/6681) just simply doesn't do TCP in java. I realize that midp2 devices are only required to support http, but I don't see why previous Nokia devices have supported sockets (e.g., 6230) while this one does not. If any official Nokia people watch this forum, could you please confirm or deny that the 6682 does not support sockets? I can't find any official word on it anywhere. Furthermore, will future firmware upgrades fix this problem?