Ching-Hsien Wang in the Libraries & Archives Support Branch of the Smithsonian's OCIO office uses Solr to index everything in the Smithsonian Collections Search Center, including the EAD finding aids I think. I'm copying Ching-Hsien because she is not on the ListServ.
Barbara D. Aikens
Chief, Collections Processing
Archives of American Art, Smithsonian Institution
aikensb @ si.edu
From: Encoded Archival Description List [mailto:[log in to unmask]] On Behalf Of Mark A. Matienzo
Sent: Thursday, April 15, 2010 11:32 AM
To: [log in to unmask]
Subject: Indexing EAD using Solr
I know there has been some discussion related to this about making EAD
available as part of the discovery layer, but I'm interested in
getting a sense of which institutions are using Solr  to index EAD.
At this point, I'm more interested in discussing the different
indexing strategies from a technical standpoint rather than focusing
too much on the discovery layer. For what it's worth, this discussion
began  when some folks were talking about incorporating EAD into a
Solr index to be used by Blacklight , an open source discovery
If your institution is using Solr to index EAD, can you briefly
describe your indexing process? I would be interested in coordinating
future work, or potentially developing a set of recommendations/best
practices to share with the community.
Mark A. Matienzo
Digital Archivist, Manuscripts and Archives
Yale University Library