Supporting CC-BY-SA 3.0 and later versions

Hi guys,                                                                                                                           
                                                                                                                                   
With http://wiki.gentoo.org having their documents as CC-BY-SA 3.0, I                                                              
thought it might be a good idea to work this out for our documents as well.                                                        
That would allow us to "tech-write" stuff that is on the wiki properly, but                                                        
also use the newer (and recommended) version.                                                                                      
                                                                                                                                   
Of course, that won't be done by just making <license /> refer to the 3.0 as                                                       
that will break our documents (legally, that is). Instead, I was considering                                                       
to add @version support to the license entity (in dtd and xsl), update the                                                         
supporting documents (xml-guide and the like) so that this can be done less                                                        
intrusively.                                                                                                                       
                                                                                                                                   
In other words, support "<license version='3.0' />" for documents that need                                                        
to be CC-BY-SA 3.0, or for new documents.                                                                                          
                                                                                                                                   
What's your take on this?                                                                                                          
                                                                                                                                   
Wkr,                                                                                                                               
        Sven Vermeulen