MacPorts: extracting to multiple locations

[John Ridgway]

Friends -
I'm working on a cleanup of the xemacs PortFile - splitting it into  
xemacs and xemacs-beta, and ensuring that without the sumo option you  
still get the base packages.  In doing this I'm discovering that I  
need to extract different distribution files into different places in  
the build tree.  Is there a standard way to do this, or can somebody  
point me to another port that does something similar?

Peace
- John