samba - Feb 2003 - Constant pings from a WIndows to Linux Samba Server Question?

I've been searching the archives, but I've not seen anything addressing
the questions I have below:

First, we run several Samba Servers on various Linux systems on our
network.  All the Samba Servers are working just fine and we are really
happy with them.

We have been trying to track down some errant pings (icmp) traffic on our
network, and we've noticed that the machines running the Samba Servers are
the ones getting hit constantly with icmp packets from all of the Windows
machines (We run from WIndows 95 to Windows XP) on our network.  We've
noticed that when we turn off the Samba Server on a machine, then the
Windows machines quit sending icmp packets to the Samba Server. I've
looked around for Windows virus advisories that might explain this, but I
have found nothing. Those Windows machines also run various Antivirus
software and the antivirus checkers have also found no signs of virus
infection.

So, my question is....Is this normal behavior for the Windows Machines to
constantly send icmp traffic to the Samba Servers on the Linux Machines?

Thanks in advance.