Slow inbound network connections after 10.6 upgrade

Hi all,

I just (finally) upgraded my MacPro to 10.6 Snow Leopard, with all the subsequent updates.

I have been running apache and PHP as a testing server, and I also screen share remotely to work on the MacPro when I travel. I have a fixed IP address at work, and my router settings have not changed since upgrading. In 10.5 everything was working perfectly -- so it is not the ISP.

Once I upgraded, however, accessing my "webserver" via my fixed IP address is painfully slow, and sometimes, times out. ScreenSharing connects after a long wait, and then drops the connection before it can even load up a screen, and ssh takes a long time to even acknowledge my attempt to connect. Again, before the upgrade, everything worked perfectly. Connecting remotely gave me no problems. Note, if I type in localhost into a web browser, there is no delay whatsoever in loading pages. Same thing with screensharing -- if I call it up over the local network via the finder, no problems, no delays. But if I access via IP, very slow and disconnects.

I think that there might be a network configuration problem or DNS issue or something with the IP address, as php and apache appear to be working fine (via localhost) but I'm not sure where to look. Any help would be much appreciated.