Removing old Windows shares from network browser

If I go to Connect to Server in the finder (command-K) and then select “Browse” I see three old Windows Neighborhoods for a network I haven’t been on in years. These do not appear in the Directory Access utility, in the Network control panel, nor any other place that I can find. They appear no matter what network I am on. They appear even when all network access is turned off (Ethernet and Airport disabled completely).

Is there a way to delete these?

Edited to add: These have appeared here for more than three years and, since I am currently on 10.6.1 client, through several major versions of OS X. They’re not harming anything but they’re annoying because they don’t belong there! I seem to remember some complicated setup involving NetInfo connecting to a Windows network which may explain why they’re there. Somewhere, there’s some config file that includes these. I just don’t know where.