I came here googling for this very same problem. I still can't click on links in ::about() box. The link appears as such (blue, underlined), but clicking on it doesnt open anything. I'm using Qt 4.5.3 on linux/gentoo, and i know the general 'open a link' stuff works from within Qt on other application (starts firefox on my computer)
I did try exactly the line quoted here.
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