The length of your fingers doesn't really affect your guitar playing, but rather, the position in which you hold your hand.

Turn your hand over, so your palm is facing up. Point your index finger away from you, parallel to the ground. Uncurl your middle finger and slightly uncurl your ring finger, and make sure your pinkie is pointing towards you...

Your hand should vaguely resemble you holding a gun, with your finger on the trigger... lol

Then, play guitar like that!

You know how Freddy Kruger holds his gloved hand out? It's like all splayed out... That's the same position...

Hope this helps :O