Anthill OS with jdk 1.3 and 1.5

Hi users

Thanks to your explanaition I can use Anthill OS with Subversion for our 
project. Most of our projects are in jdk1.5. But we have still some 
project in jdk1.3. And my question is this following, can we make some 
change with ant script or with anhill , in the way to produce night 
buildings with all projects although there are two different jdks?
What could be your solution ?
thanks in advance for the answer
BR
alex