Alt-tab on kde 4.8.1

[Chris Rouch]

I recently updated to kde 4.8.1 on fedora 16, and notice that Alt-Tab
no longer works. In the settings window, I have this set to "walk
through windows". The top half of this is greyed out with a message
"Focus policy settings limit the functionality of navigating through
windows.", but previously (kde 4.7.4) this action would raise the next
window. The focus policy is "focus under mouse".

Is there a way to make alt-tab work again?

Regards,

Chris