Contact Lists

Hello,

I have just read through the WIKI pages for Zoho CRM and I cannot seem to find a solution to the following problem.

I basically want to be able to structure my contacts into contact lists. A contact should also be able to be a member of several lists and a list can be a "sublist" of another list.

Is that possible to do? If you can point me to any document that explains how to do that, that would be great!
Thanks,
Jen.