Misconfigured "confFiles" entry in solrconfig.xml

I'm not sure where the value for "${confFiles}" is supposed to come from, but in apachesolr-7.x-1.2, solr-conf/solr-4.x/solrconfig.xml, line 1076:

<str name="confFiles">${confFiles}</str>

causes my Jetty server to crash. I wasn't sure what the problem was at first but this is the line in apachesolr-7.x-1.x-dev solrconfig.xml as of today:

<str name="confFiles">${solr.replication.confFiles:schema.xml,mapping-ISOLatin1Accent.txt,protwords.txt,stopwords.txt,synonyms.txt,elevate.xml}</str>

Obviously a very different value for this string. I searched the issue queue for "confFiles" but no one else seems to have run into this.

I am using Solr 4.3.0 from the Apache tarball, with Jetty 6.1.24-6ubuntu0.12.04.1 (amd64)