I am having a random "connection refused" error from my java application. Sometimes it's fine, apps running without any problem, but sometimes this exception comes up. I am writing this app at home and my SQL server is at office (behind a router with SPI firewall, but i have port forwarded TCP port 1433 for the connection). If I telnet to SQL server, i wont get any error message but a blank screen, it looks like the server side is waiting for my console input.

IDE: NetBeans IDE 6.0 (Build 200711261600)
JavaSDK: 1.6.0 build 1.6.0_03-b05
MSSQL JDBC Driver: should be latest (i downloaded off from MS website in early March)
MSSQL: MS SQL 2005 Developer Edition

com.microsoft.sqlserver.jdbc.SQLSe* rverException: The TCP/IP connection to the host has failed. java.net.ConnectException: Connection refused: connect

any help would be appreciated