This was driving me crazy!! Every time I'd try and use nm-applet to configure my wireless internet with WPA, it would connect, but then be unable to save or retrieve the password afterwards. Grr! That essentially caused it not to work at all.
Thankfully, I was able to fix it. Thanks to the Ubuntu forums (Ubuntu is based off of debian), I found a solution which worked for me. I moved the keyring folder inside of ~/.gnome2/, and then tried again. It asked me for a new password, and so far so good!
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