replication not working between 1.4.1 and 3.1-dev

[Shawn Heisey]

I started to upgrade my slave servers from 1.4.1 to 3.1-dev checked out 
this morning.  Because of SOLR-2034 (new javabin version) the 
replication fails.

Asking about it in comments on SOLR-2034 brought up the suggestion of 
switching to XML instead of javabin, but so far I have not been able to 
figure out how to do this.  I filed a new Jira (SOLR-2204) on the 
replication failure.

Is there any way (through either a config change or minor code changes) 
to make the replication handler use XML?  If I have to make small edits 
to the 1.4.1 source as well as 3.1, that would be OK.

Thanks,
Shawn