Rated 5 out of 5 stars

by slumbergod on Jan. 9, 2011 ·

As someone else suggested, try going to the home page for the developer and manually upgrade to 0.6.1
This fixed the problem for me so chances are it will help a lot of others too.
(right click on status bar gmail manager icon and select Go To Homepage)

This review is for a previous version of the add-on (0.6).