|Error committing transaction:; nested exception is: Exception [EclipseLink-7027] (Eclipse Persistence Services – 2.0.2.v20100323-r6872): org.eclipse.persistence.exceptions.ValidationException Exception Description: The sequence named [ATTEMPT_TYPE_SEQ] is setup incorrectly. Its increment does not match its pre-allocation size.
try chaging the pre-allocation size value (toplink map->Database Info tab->Sequencing).
If you are using Oracle db, also make sure that you database sequence increment and TopLink sequence preallocation sizes are the same.
For more info refer to http://www.oracle.com/technology/products/ias/toplink/doc/1013/main/_html/prjdaun007.htm
Hope this helps,