The gnome panel CPU scaling applet doesn't work anymore

[ZankerH]

I've recently re-installed ubuntu on my laptop, and it appears I've somehow lost the fonctionality of the CPU scaling applet: it displays the current frequency, but I can't get the menu to display by left-clicking on it. The CPU frequency does scale (it appears to be on "on-demand" mode"), but I can't set it manually. There is no issue with left-clicking any of the other panel items.

Could anyone help me pinpoint the source of this problem?

[Yellow Pasque]

Most likely, you don't have cpufrequtils installed.

sudo apt-get install cpufrequtils

[Ocxic]

sudo chmod +s /usr/bin/cpufreq-selector will let the applet do it's thing.