Hey, sorry that your game did not come up to one of the first positions. I love it that much that i ported it to Delphi. No kidding, but the cpu fan on my laptop is extremely nagging while using java.
It seems to be working like the original, but somehow the ai is much too passive. I guess there is some sort of typo, maybe you could have a look?
I uploaded the source and the binary to:
http://www.mediafire.com/?sbhb1n0sjfnql9s
Peter
I’m flattered. 
Have you considered replacing the targeting code with something like “attack the first planet you can attack” and then building up from there? My code is fairly terrible anyway.
BTW, try the code at https://gist.github.com/848867/ - it should now be much less of a drain on your CPU, as it will only update when needed.
I did not considered changing the algorithm at all, at least unless i find the reason why the ai is not working similar like in the java original. My guess is that it might be caused by the loops and goto constructs you made. Since i stopped dealing with basic (15 years ago), i tried to avoid labels 
The new update code should help a bit, but in my case the fan always start once java is loaded. Its java related i guess