Have a look at this nice one (alert log), seen in 10gR2 (10.2.0.4 64bit on Linux):
ORA-00600: Interner Fehlercode, Argumente: [kgeade_is_0], , , , , , , 
And from the trace file:
Current SQL statement for this session: select tablespace_id, rfno, allocated_space, file_size, file_maxsize, changescn_base, changescn_wrap, flag from GV$FILESPACE_USAGE where inst_id != :inst and (changescn_wrap >= :w or (changescn_wrap = :w and changescn_base >= :b))
<stack traces en masse>
kxfpgsg Error 600 encountered error 600 detected in background process OPIRIP: Uncaught error 447. Error stack: ORA-00447: fatal error in background process ORA-00600: Interner Fehlercode, Argumente: [kgeade_is_0], , , , , , , 
Context: One RAC node (of two) worked well, the other one did as described immediately after restarting the instance (I guess during the instance recovery process).
Neither Metalink nor Google seems to know this one. We will see.