When the battstat_applet is running, every once in a while it will pop up an information message in a window with the title 'Information'. This message the window displays is always 'Battery is now fully re-charged!' This happens even when the battery isn't full.. my battery is now at 70% and I just got this message. This problems happens repeatedly, and it never pops up a window that has a different message. The best way to reproduce the problem is to just run the applet on a laptop for a while. I think the messages like to show up when the battery percentage hits a percentage that's divisable by 10. Even though the pop-up windows don't display the proper battery status, the part in the panel does display the proper battery status.
Fixed in gnome-applets-1.4.0.1-6