I have really small hands, and short fingers. On a piano I can reach an octave and a little more, but my octave is generally very sloppy. A lot of songs require some crazy octaves like Liszt's Liebestraum. The part where the melody is played by octaves and leads up to the cadenza(I think that's what it's called). Also, like Revolutionary, the main melody is octave. I generally just lower my hand a little bit and point my hand upward then play with the edge of my fingers. It's doable but inconvenient. I can generally play chords that span an octave, but can't play the octave well...so I doubt there's anyway around it unless I get surgery on my hands or something.
It sounds like my fingers are a similar length to yours. I found that the important part of reaching the octaves confidently was flexibility rather than length. Your thumb and pinky finger (or even your ring finger) can bend back further than you might think. Never force it though. As with most aspects of playing, I'm afraid it just takes time and practice to stretch comfortably.
Try playing octave scales regularly to get your hands used to it. Also try playing scales using 7th and 9th intervals (instead of octaves). It doesn't sound very tuneful, but it can help build up your strength and accuracy. From there, try running up and down scales playing full octave chords (i.e. play the major chord for whatever your root note is... e.g. C major, D major, E major, and so on). If you're feeling adventurous, try playing 1st or 2nd inversions instead so you get used to your hand being at slightly different angles.
Always warm up a little with scales etc. before you do the stretching though, and go slowly at first. You need accuracy before building up speed. Also, try to keep your hand relaxed at all times so you can stretch safely. Given enough time, you might be surprised by how far your fingers will reach.