Strange Traffic to ports 139 and 137 from a machine with no data

Hello all,
 I have a machine that is sending out empty data packets destined to random ip addresses with a destination port of 137 and 139.  All the IP Addresses seem to be a military and NOC location.  I have attached some of the IP's below.  I have ran antivirus, anti-spyware and rootkit detectors (sysinternals, and f-prot) all came up empty.  I had found one other person on the internet that seemed to have this problem, but no resolution. Any ideas?

132.118.36.8
132.127.246.104
132.138.128.168
132.140.183.168
132.146.63.104
132.149.222.200
132.155.92.8
132.159.181.104
132.187.216.72
132.191.199.8
132.197.155.8
132.203.77.232
132.205.80.8
132.214.49.104
132.218.106.40
132.219.200.72
132.220.251.232
132.223.78.8
132.225.62.8
132.243.250.200
132.255.206.104
132.42.104.200
132.60.179.232
132.60.179.232
132.75.19.200
132.80.210.72
132.85.219.136
132.88.7.40
132.91.182.72
133.100.223.104
133.116.3.40
133.116.82.200
133.121.101.72
133.171.34.104
133.185.90.112