Similar issues rejected: HHH-1007 Closed HHH-5569 Closed HHH-6726 Closed HHH-7737 Closed . But these seem to concern Oracle10 dialects and earlier. Maybe there was some issue with the drivers back then too?
A similar suggestion came up here: HHH-6066 Closed , but ultimately only Postgres was fixed it seems.

This open ticket is likely caused by using "long" as default for lengthy strings: HHH-9526 Awaiting Response