Dear Christian and Richard,
 
Based on the GiNaC, we have implemented the multivaritate factorization, and embeded in our CAS, CMCL.
 
The CAS/CMCL we built is also on the basis of your open-source symbolic package, GiNaC. And it is compatible with the CAS/Maple's program language. 
 
If you and other developers are interested in our CAS/CMCL, please visite the site:
http://www.acailab.com/cmcl/cmcl-index.htm
 
Also, as an open project,  it is very thankful for you and all the other developers to take part in it. What is more, we need your help , because some problems are not been solved until now, which have been enumerated in the To-Do list.
 
 
Thanks,
 
Qin An