Comment 2 for bug 467068

Confirming this on my Kubuntu Karmic AMD64 install, here's what I did and experienced:

I started oocalc and created a link to http://www.kubuntu.org/ in the topleft cell. I clicked the link while my browser was open. I had previously set firefox as my default browser and this correctly opened this link in a new tab. Calc however displays an error message saying that no browser could be found.

Second situation I tested was with firefox not running, when clicking the link, firefox is opened, but the error message is not yet shown. The spreadsheet cannot be edited however. When closing firefox again, the error message that a browser could not be found appears. When closing this error the spreadsheet is usable again.