DBConsole Shows Listener and Database Down If Not Using Default Values

Oracle Database 10g dbconsole is configured for default port usage and default listener name.
(Port=1521, listener name is LSTENER)
If database uses different port number and listener name, everything will shown down in dbconsole.

To solve this issue action plan is below.

1. emcl stop dbconsole
2. Change related parts of mentioned files 
1. $ORACLE_HOME/hostname_SID/sysman/config/emoms.properties
2. $ORACLE_HOME/hostname_SID/sysman/emd/targets.xml
3. emctl start dbconsole