I have a new DIR-825 with the latest firmware. Everything seems to be working fine, however, my Network and Sharing Center (Vista) is populated by two wireless connections at the same time. One shows up as a Private Network with my correct SSID only it has a space and the number 4 added to the SSID. A second simultaneous connection is listed also and described as Unidentified Network (Public network).
For both connections, my correct SSID is listed in parenthesis after the "Connection" "Wireless Network Connection" line. If I disconnect one, the other goes away and vice versa.
FYI, this is on the 2.4GHz band only, the 5GHz band is a different SSID altogether.