SL constantly making DNS requests for "local" ?

I've been troubleshooting a problem with my DSL router crashing and noticed that my Macs continuously, even when idle, have nearly 200 open connections at any given time, whereas my Windows boxes peak at 50 and drop down to under 10 when idle. The Macs are running SL 10.6.2.

Poking around in the router logs, I found that the Macs are constantly making udp DNS requests to my router, even when I'm not browsing or doing anything else. tcpdump of udp and port 53 gives me the following:

00:21:53.371671 IP 192.168.0.8.59304 > 192.168.0.1.53: 18151+ SOA? local. (23)
00:21:53.674232 IP 192.168.0.8.49916 > 192.168.0.1.53: 48169+ SOA? local. (23)
00:21:53.977128 IP 192.168.0.8.52735 > 192.168.0.1.53: 25906+ SOA? local. (23)
00:21:54.279836 IP 192.168.0.8.60409 > 192.168.0.1.53: 18252+ SOA? local. (23)
00:21:54.582518 IP 192.168.0.8.52350 > 192.168.0.1.53: 61085+ SOA? local. (23)
00:21:54.885866 IP 192.168.0.8.62450 > 192.168.0.1.53: 21082+ SOA? local. (23)
00:21:55.189449 IP 192.168.0.8.56146 > 192.168.0.1.53: 32869+ SOA? local. (23)
00:21:55.494834 IP 192.168.0.8.50517 > 192.168.0.1.53: 19194+ SOA? local. (23)
00:21:55.797551 IP 192.168.0.8.52035 > 192.168.0.1.53: 7558+ SOA? local. (23)
00:21:56.100390 IP 192.168.0.8.52101 > 192.168.0.1.53: 40847+ SOA? local. (23)
00:21:56.403436 IP 192.168.0.8.52194 > 192.168.0.1.53: 6087+ SOA? local. (23)
00:21:56.706299 IP 192.168.0.8.52347 > 192.168.0.1.53: 9339+ SOA? local. (23)
00:21:57.009058 IP 192.168.0.8.56200 > 192.168.0.1.53: 25553+ SOA? local. (23)
00:21:57.312098 IP 192.168.0.8.51976 > 192.168.0.1.53: 20703+ SOA? local. (23)
00:21:57.616665 IP 192.168.0.8.54563 > 192.168.0.1.53: 54141+ SOA? local. (23)
00:21:57.923536 IP 192.168.0.8.65097 > 192.168.0.1.53: 45734+ SOA? local. (23)
00:21:58.226243 IP 192.168.0.8.54125 > 192.168.0.1.53: 33647+ SOA? local. (23)
00:21:58.529128 IP 192.168.0.8.54571 > 192.168.0.1.53: 17218+ SOA? local. (23)
00:21:58.831897 IP 192.168.0.8.60218 > 192.168.0.1.53: 48469+ SOA? local. (23)
00:21:59.135020 IP 192.168.0.8.60466 > 192.168.0.1.53: 37003+ SOA? local. (23)
00:21:59.437998 IP 192.168.0.8.58798 > 192.168.0.1.53: 17670+ SOA? local. (23)
00:21:59.741022 IP 192.168.0.8.60276 > 192.168.0.1.53: 47469+ SOA? local. (23)
00:22:00.055207 IP 192.168.0.8.57066 > 192.168.0.1.53: 20384+ SOA? local. (23)
00:22:00.360458 IP 192.168.0.8.50152 > 192.168.0.1.53: 29721+ SOA? local. (23)
00:22:00.663357 IP 192.168.0.8.63487 > 192.168.0.1.53: 35833+ SOA? local. (23)
00:22:00.966073 IP 192.168.0.8.64900 > 192.168.0.1.53: 34951+ SOA? local. (23)
00:22:01.271649 IP 192.168.0.8.64314 > 192.168.0.1.53: 25719+ SOA? local. (23)
00:22:01.574530 IP 192.168.0.8.55922 > 192.168.0.1.53: 5842+ SOA? local. (23)
00:22:01.877146 IP 192.168.0.8.51874 > 192.168.0.1.53: 59071+ SOA? local. (23)
00:22:02.179921 IP 192.168.0.8.56913 > 192.168.0.1.53: 43487+ SOA? local. (23)
00:22:02.482738 IP 192.168.0.8.62907 > 192.168.0.1.53: 26628+ SOA? local. (23)
00:22:02.785409 IP 192.168.0.8.51599 > 192.168.0.1.53: 57463+ SOA? local. (23)
00:22:03.088321 IP 192.168.0.8.60417 > 192.168.0.1.53: 8857+ SOA? local. (23)
00:22:03.391227 IP 192.168.0.8.57872 > 192.168.0.1.53: 36002+ SOA? local. (23)
00:22:03.694211 IP 192.168.0.8.58774 > 192.168.0.1.53: 1662+ SOA? local. (23)

192.168.0.8 is my Mac and 192.168.0.1 is my DSL router. The Mac is ip'd using DHCP on the router. The router sends DNS requests from my clients out to my ISPs DNS servers.

Eventually, the DNS requests timeout and I get this:

00:21:43.145103 IP 205.171.3.65.53 > 192.168.0.8.52959: 38258 NXDomain 0/1/0 (98)
00:21:43.450086 IP 205.171.3.65.53 > 192.168.0.8.55938: 46832 NXDomain 0/1/0 (98)
00:21:43.763304 IP 205.171.3.65.53 > 192.168.0.8.50265: 62399 NXDomain 0/1/0 (98)
00:21:44.049705 IP 205.171.3.65.53 > 192.168.0.8.59991: 5960 NXDomain 0/1/0 (98)

It's a never-ending cycle that eventually kills my router.

If I'm reading the tcpdump output correctly, SL appears to be looking for some server named "local" 3 times every second. The TTL is roughly 90 seconds, so 3 requests/second gets me to an average of 180 connections at any give time -- which is approximately what my router is showing. If I do start browsing the connection count goes even higher. Trying to use both Macs at the same time has caused my router to crash due to running out of memory (it's obviously a very weak router 😉.

Can someone give me some insight into what SL is doing and how I can stop this?

Thanks,

Randy