Just re-built latest svn of 1.9.0 and base64.rb is removed.  Its  
required in active_support (conversions.rb).  Do you think its worth  
having all libraries that were removed from Ruby in 1.9.0 moved into a  
"legacy gem" or something?  I am sure the rails guys will catch this  
and remove the dependency since its not going to be supported going  
forward, but this kind of thing may happen to other libraries.

Best,

Rich

PS.  Great work Matz and team...Merry Christmas!