Thanks for your testing and finding this bug. I can confirm that this bug exists in Karmic.
Steps to reproduce: Karmic Live CD (Power Manager Inhibit Applet version 2.27.1) Add "Power Manager Inhibit Applet" to the top panel click on the icon
what happens: nothing
what should happen: the icon adds a red circle with a line through indicating that the inhibit applet is active.
Thanks for your testing and finding this bug. I can confirm that this bug exists in Karmic.
Steps to reproduce:
Karmic Live CD (Power Manager Inhibit Applet version 2.27.1)
Add "Power Manager Inhibit Applet" to the top panel
click on the icon
what happens:
nothing
what should happen:
the icon adds a red circle with a line through indicating that the inhibit applet is active.