I am using Jboss 3.0.6 with sybase ase 12.5 (JConnect 5.5). When backend database restart (after failure), connection to the database server is allowed but individual database cannot be accessed until recovery complete. Under such a situation, the "master" database is used (a warning message is displayed) even though the database name is correctly speciified in the URL.
Since connection pool is used, the connection (with incorrect database) will not released and caused error when it is used by the application (e.g., table not found). Connection created after database recovery is okay.