I have been playing electric for almost two years now, but I received an acoustic last Christmas. Now I haven't played the acoustic as much as I should, but I do pick it up and play it every so often. The problem I have been having is that whenever I play my acoustic, my finger tips start to get bruised and sore. There is no problem when I play any of my electric guitars, and I play those for a couple of hours everyday.

If anyone can give me any info on why this is happening and what I can do to change this.

its just the tips of your fingers getting used to the rougher acoustic strings. I got this when i started to play bass a year ago, you just have to keep with it, soon your fingers will get used to it and your finger tips will become harder and more callas as the skin hardens at which point you should feel any more pain! So basically man up!