Had quick look at the ports, it is defined for NETBIOS. so I suspect it will be used by Samba. Do you have Samba installed and running?
To have a service "listen" on a port it needs to be defined somewhere, either as a standalone service started from the runlevels (start/stop script lives in /etc/rc.d/init.d) or from the inetd service. (services are defined/configured in /etc/xinetd.d/ directory)
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