I recently upgraded my firmware from 1.32 to 1.33, and this error popped up when trying to setup my wireless. I spent a fair bit of time searching for a solution and found one:
For simplicity sake, use IE8 to go to your DIR655 page.
* If your wireless was disabled, you will need to reset the router to default settings to renable it.
* Go to Advanced -- Wireless Advanced
* Now, on your IE8 Toolbar, select Page in the top left corner, then Style -- No Style.
* The page will get very ugly, but if you scroll down, you will see WDS settings, and 5 MAC address fields, all populated with 00:00:00:00:00:00.
* Erase all of the MAC addresses, so the fields are blank.
* Find the Save Settings near the top, and if it asks for a reboot, do it.
You should now be able to change your wireless settings.
It worked for me, so good luck!