For those of you interested, here are some articles that discuss climbing techniques while standing.
Something very few people do, and even harder to mimic on a spin bike, is using the bike to your advantage. While you’re climbing, torque the bike underneath you to give you leverage in your downstroke. This is where, contrary to popular belief, cyclists need at least moderate upper body strength.
Other philosophies (although not really followed by carmichael) is to bring your center of gravity forward of the pedal axel. This allows you to get the most leverage on the upstroke, as well as the most leverage on the downstroke as you push more fully through the pedal stroke.
Anyways, read these articles, and practice some of the techniques on the spin bike. In reality, you wont gain the techniques of climbing until you ride 20-25 km climbs on a consistent basis, but at least you can work on it and apply it in the upcoming races.
http://www.roadcycling.com/cgi-bin/artman/exec/view.cgi/4/558
http://www.howtobefit.com/climbing-tactics.htm
http://www.roadcycling.com/news/article1429.shtml
While taking the knowledge of these articles as much as possible, also realize they are personal philosophies as to what works best. Many say climb only seated, others say only standing, others say both. You have to find your own rhythm and what works best for you. Rasmussen made it evident that you can destroy climbs while seated (drug usage aside), Contador showed that a good surge of standing on a climb can gain you some serious time and distance. Lance Armstrong destroyed Alp d’huez seated, but rode most of the Pyrenese standing.
Find what works best for you, but just make sure you do it RIGHT!
-Mike