FTS-lucene errors : language not available for stemming

I'm getting some log errors with clucene that I am having no luck tracking down on the interwebs.

Errors:

May 19 05:05:16 indexer-worker(gessel@blackrosetech.com)<62971>: Error: lucene index /mail/blackrosetech.com/gessel//lucene-indexes: IndexWriter::addDocument() failed (#4): language not available for stemming May 19 05:05:16 indexer-worker: Error: May 19 05:05:16 indexer-worker(gessel@blackrosetech.com)<62971>: Error: Mailbox Security: Mail search failed: Internal error occurred. Refer to server log for more information. [2020-05-19 05:05:16] May 19 05:05:16 indexer-worker(gessel@blackrosetech.com)<62971>: Error: Mailbox Security: Transaction commit failed: FTS transaction commit failed: transaction context (attempted to index 1 messages (UIDs 152736..152736))

Config:

FreeBSD 11.3-RELEASE-p8 #0 r360490

dovecot-2.3.10_3

clucene-2.3.3.4_19

py37-pystemmer-2.0.0.1

py37-snowballstemmer-1.2.1

icu-67.1,1

plugin { #setting_name = value expire = Trash mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename mail_log_fields = uid box msgid size fts_autoindex=yes #zlib_save_level = 6 # 1..9 #zlib_save = gz # or bz2 }

plugin { fts = lucene # Lucene-specific settings, good ones are: fts_lucene = whitespace_chars=@. mime_parts }

I am considering switch to xapian (solr and java... pls noe) as the port is quite tempting from an ease of integration perspective, but the easiest solution would be to resolve these odd indexing errors.  Anyone have a clue?

-David