In reply to SaulGilsenan:
yeah like the other guys say: training fingers and forearms, and developing back and core whilst at the wall/crag.
me, i think it all connects, so stuff that pulls it all together from hands and fingers to the big muscle groups that are the 'core '(jeez i loathe that word).
for climbing hard you want precision and recruitment power too, along with actual contact strength. full body lifts can help there - but off set them or use kettlebells or something to show up any left/right imbalances.
my personal favourite is suspended presses - not much to do with regular presses at all, but connects right thru the body (basicly drop back to horizontal on a GHD and press a kettlebell from armpit to full extension).
but again, being a press its not too directly applicable, more as a body integrity thing.
overhead squats are another good one.
plyometric pushups and overhead holds to train pump and recovery are good too.
nothing wrong with just training to get stronger in general