Arduino Linux problems

Hi All

We are using software that is doing connection via Socket technology. We have Arduino Duemilanove and Aruidno Ethernet Shield and SKD that we wrote into via Telnet. We have no problem with connection to Windows server, where is running our Java aplication. When we connect to Linux, Ubuntu 13.04 32 or x64 versions we get next problems. After loading software on server Arduino connects with out any problem, but when we reset Arduino - Arduino doesn't reconect to server and freeze.

who connects who? Does the arduino runs a TCP socket server or is the PC?

Arduino connects server and TCP Socket Server runs on Arduino. First connection we have no problem, problem accrues if Arduino lost connection - it doesn't reconnect to server.

Can anyone help us?