Google has a lot of hits on
+"invalid authorization specification" +tomcat
The solution often suggested is to GRANT access privileges on a per-database-level. Some solutions even suggest editing the mysql tables directly. The whole thing is a bit too mysterious for my taste. The Tomcat developers should probably think of having a resolution for this problem on their website.
If you grant privileges on a TABLE level instead of a DATABASE level, for some strange reason, the access is given.
GRANT SELECT, INSERT, UPDATE, DELETE ON somedatabase.sometable TO someuser IDENTIFIED BY 'somepass';
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