Problem with solr indexing: group_concat() does not exist

[ecs-hk]

I'm testing with the latest (as of this writing) Checkbook commit - 4b1eb4940bf43.

After following the install and solr-install instructions, I attempt to run solr indexing with an HTTP request to "http://localhost:8080/solr-checkbook/dataimport?command=full-import&clean=true&jobID=0"

I tail the catalina.out file, and all looks good until it hits this error:

Caused by: org.postgresql.util.PSQLException: ERROR: function group_concat(integer) does not exist Hint: No function matches the given name and argument types. You might need to add explicit type casts.

I checked /opt/solr-4.1.0/indexes/solr/collection1/conf/db-config.xml and I see that there are indeed GROUP_CONCAT() function calls. I am not a PostgreSQL expert, but a quick review on the 'net shows that this is a MySQL (not PostgreSQL) function.

Am I missing something? Are others running their solr indexing against a PostgreSQL DB with GROUP_CONCAT() calls (in db-config.xml) successfully?