RMAN duplicate database fails with RMAN-00601, RMAN-10006, ORA-00704, ORA-39700

Problem Description
Duplicating database using RMAN fails with following errors.

channel channel1: starting piece 1 at 29-JUL-2010 03:49:19
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00601: fatal error in recovery manager
RMAN-03004: fatal error during execution of command
RMAN-10039: error encountered while polling for RPC completion on channel channel1
RMAN-10006: error running SQL statement: select action from gv$session where sid=:1 and serial#=:2 and inst_id=:3 
RMAN-10002: ORACLE error: ORA-3114: not connected to ORACLE 
RMAN-10041: Could not re-create polling channel context following failure. 
RMAN-10024: error setting up for rpc polling 
RMAN-10005: error opening cursor 
RMAN-10002: ORACLE error: ORA-3114: not connected to ORACLE 
RMAN-03002: failure of Duplicate Db command at 02/23/2007 11:11:50 
RMAN-03015: error occurred in stored script Memory Script 
RMAN-06136: ORACLE error from auxiliary database: ORA-1092: ORACLE instance 
terminated. Disconnection forced 
ORA-00704: bootstrap process failure 
ORA-39700: database must be opened with UPGRADE option

Cause of the Problem
The errors occurred because the Oracle versions for both the target database home and the auxiliary database home are not same.

Solution of the Problem
The solution is to upgrade the auxiliary database server binaries to match the target database server. Also if there is one off patches that exist on the target database, you also need to apply on the auxiliary database in order to make the duplication work.