I am upgrading from 11.1.0.7.0 to 11.2.0.3 with R12.1.3 while pre upgrade/catupgrd.sql erroring out ORA-00600 While upgrading from 11.1.0.7.0 to 11.2.0.3 with R12.1.3, during running the pre upgrade script catupgrd.sql, it is erroring out

ORA-00600: internal error code, arguments: [qcisSetPlsqlCtx:tzi
 init], [], [], [], [], [], [], [], [], [], [], []


I applied patch 10272702, the patch got applied successfully but still the persist.
This problem is related to timezone stuff. Did you execute the pre-upgrade (utlu112i.sql) scripts? And did you follow the instructions?