Foundation Character Rigging
Standard biped and quadruped character creation just got easier in XSI v.4.2 Foundation, with a new streamlined workflow. In one place you can access all your rigging guides as well as generate film quality rigs.
http://www.softimage.com/products/xsi/v4/features/
This video will demonstrate nicely how easily you can do things with XSI:
http://www.softimage.com/downloadsrv/process.asp?file=/Videos/v4/Foundation_Characters.zip
Here's the comparision of the packages:
http://www.softimage.com/products/Xsi/v4/comparison/default.asp
Foundation is missing in character department only the "Advanced Rigs, Guides and Characters" but it has "Standard Biped and Quadruped Rigs and Guides".