Shadows and light

Help me, internets, you’re my only hope.  (Sorry, it was a gimme, we’ve had Episodes IV and V on since I got home from work.)  Anyway, I’m reasonably good with photo editing software.  I’m self taught, I can do interesting and useful things like remove items, clean up red eye, change brightness and contrast, etc.  I have, however, run into a problem that I can’t solve.

I have a wedding photo taken of us back on the day of that I like very much.  The problem is that there’s a shadow cutting right across Geoff’s face and I just don’t know how to remove it.  I can kill shadows on other surfaces pretty competently, but for some reason I am having trouble doing this without making Geoff look like a leper, zombie, or like he has some other really unfortunate skin disease.

Here’s the photo.

I have an old version of Photoshop, Picnik, and an assortment of other free software type things like GIMP.  Any suggestions as to what I should do to make this shadow go away?  I’d like to print this photo without half of Geoff’s face looking like it is hiding and I’m tired of messing with it.

Thanks for any tips you can offer, folks!

~Kelly