"Local Passwords File Corrupted"

I keep getting this error when I open up a new Firefox window:

"myVidoop Plugin Error: Sorry, your local passwords file looks corrupted. Please start a new file."

That's odd. myVidoop is recording passwords and retrieving passwords from the myVidoop web service just fine. I'm really not sure why this problem would effect me at all, but that error keeps showing up - and it's annoying to see.

So I went to the myVidoop web service and generated a new passwords file. I downloaded it to my Mac, and found the directory it belongs in. I had to dig into my ~/Library/Application Support/Firefox/... folders looking for the myVidoop plugin folder. That's common sense to me, but for some people it wouldn't be.

Anyway, I replaced the .pws file that was listed as myusername.pws, with the new password file, which I named the same thing. I restarted Firefox, and I'm still getting this error.

Any idea why? :(

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In case this is important, I'm running:

Mac OS X 10.5.4 with Firefox 3.0.1.

Extensions I'm running are:

Adblock Plus 0.7.5.5
Delicious Bookmarks 2.0.95
Firebug 1.2.0
Google Gears 0.4.15.0
Greasemonkey 0.8.20080609.0
myVidoop Plugin 1.0.4
Operator 0.9.3
TimeTracker 1.2.4