historical port usage information

are there linux commands or applications that i can use to find out what application was using a certain port at a certain time? there's teamquest,but it doesnt have this kind of information.

TIA.

Not that I know of. Maybe Nagios or Snort could provide such an information (not sure), but history's history. You'd probably be quicker to write a simple shell script that uses netstat to record that information for you.