A rather not so great post about an ORA-00600 error i faced on a standby database. Environement was 22.214.171.124 on Sun Super Cluster machine. MRP process was hitting ORA-00600 while trying to apply a specific archive log.
The error message was something like this
MRP0: Background Media Recovery terminated with error 600 Errors in file /u01/app/oracle/product/126.96.36.199/diag/diag/rdbms/xxxprd/xxxprd1/trace/xxxprd1_pr00_6342.trc: ORA-00600: internal error code, arguments: , , , , , , , , , , ,  Recovery interrupted!
Some googling and MOS searches revealed that the error was due to corrupted archive log file. Recopying the archive file from primary and restarting the recovery resolved the issue. The fist argument of the ORA-600 is actually the sequence no of the archive it is trying to apply.