help! Strange traffic

[Karan Gupta]

Hi
  Im running a fBSD T1 router(a gatewat with a sangoma 514 csu/dsu card) 
that performs dhcp, nat, ipfw firewall.
FreeBSD rtr-eee.eeee.com 4.8-RELEASE FreeBSD 4.8-RELEASE #4: Thu Jul 31 
04:47:04 PDT 2003     root@:/usr/src/sys/compile/GENERIC  i386

Im seeing the following traffic on doing tcpdump on the external interface
01:12:15.875308 201.93.36.43.1913 > web.visp.ashosting.nl.http: S 
1396310016:1396310016(0) win 16384
01:12:15.876288 201.93.36.41.1587 > web.visp.ashosting.nl.http: S 
802357248:802357248(0) win 16384
01:12:15.885340 201.93.37.127.cuillamartin > web.visp.ashosting.nl.http: 
S 1656750080:1656750080(0) win 16384
01:12:15.886056 201.93.36.250.1194 > web.visp.ashosting.nl.http: S 
1188954112:1188954112(0) win 16384
01:12:15.886794 201.93.36.118.1613 > web.visp.ashosting.nl.http: S 
474546176:474546176(0) win 16384
01:12:15.887628 201.93.36.120.1135 > web.visp.ashosting.nl.http: S 
224526336:224526336(0) win 16384
01:12:15.895344 201.93.37.129.1073 > web.visp.ashosting.nl.http: S 
5767168:5767168(0) win 16384
01:12:15.896286 201.93.37.131.timbuktu-srv3 > 
web.visp.ashosting.nl.http: S 2056323072:2056323072(0) win 16384
01:12:15.905302 201.93.37.225.1341 > web.visp.ashosting.nl.http: S 
2125070336:2125070336(0) win 16384
01:12:15.906042 201.93.37.223.docstor > web.visp.ashosting.nl.http: S 
1558642688:1558642688(0) win 16384
01:12:15.915253 201.93.38.91.1842 > web.visp.ashosting.nl.http: S 
1312751616:1312751616(0) win 16384
01:12:15.916105 201.93.38.89.1326 > web.visp.ashosting.nl.http: S 
1620377600:1620377600(0) win 16384

The 201.x.x.x is NOT from my local network. That would mean that 
web.visp.ashosting.nl is being hosted on my network(weird!!)) ???? This 
name doesnt resolve to any IP address either. How do i block this. I 
tried blocking 201.93.0.0/16 but then the traffic started coming from 
195.x.x.x

Help!!!!!!