I have a problem connecting to a MSSQL server (version 7). I'm trying to connect from a Linux box to port 1433 using a JDBC driver (both FreeTDS and Microsoft's own driver), but both fail, reporting something like

"Error establishing socket"
"Network error: Connection refused"

Just telnetting to port 1433 simply doesn't work, so the server obviously isn't listening on that port. I've checked the firewalls and they aren't the problem. This system did work a few months back, but has now stopped working.

There's another MSSQL server in the network, which accepts connections from the same computer, program and JDBC driver, so the problem isn't client-side.

Windows clients connecting to the server (without any problems, I might add) have the property "Dynamically determine port" turned on.
TCP/IP support on the server should be activated, as well as named pipes (which the Windows clients probably use). I'm not the administrator of the database server, so I can't doublecheck and the administrator is overly busy anyways.

The control port (1434) doesn't respond to requests either. I'm at a loss. How am I supposed to connect to a server that doesn't have its ports opened? Any help would be truly appreciated.