[Info-ingres] Jdbc 'Invalid locator specified' exception

[nikosv]

I'm writing an XML file as BLOB through Hibernate.While it saves alright
when trying to retrieve it (as a binarystream) it always throws error 
'Invalid locator specified'

specs:
Jdbc driver Version 4.4.2
Ingres version  II 10.2.0 (a64.lnx/100)

the log files do not say much.Can somebody help? thanks 
Note there's no problem with the code because it works 'as-is' on Oracle 12c.