Solr 4.4 and Google Protobuf

[Guido Medina]

Hi,

I saw inside the solr.war file there is a protobuf version 2.4.0a, I 
have two questions about it:

1. Where does Solr uses protobuf? And is it better than HTTP?
2. Why is it such an old version if protobuf recommended versions are
   2.4.1 and 2.5.0 - 2.5.0 has an extra 25% performance over 2.4.1
   according to release notes:
   http://protobuf.googlecode.com/svn/trunk/CHANGES.txt

Thanks,

Guido.