Exadata X4-2 -- EBS Scan Listener Registration Problem

When using EBS with Exadata, you may encounter a problem with the remote database listener registration.. That is scan listener registration..
Even if your have remote_listener parameter is set and scan listener is configured and running properly, you may see that your database is not registered with the scan listener..
If that 's the case ; set your "ORA_NLS10" environment using "srvctl setenv" and restart your database..
After this action, you will see your database registered with scan listeners.. 
Set your TNS_ADMIN environment variable, as well (just in case)

Example
srvctl setenv database -d LIVE -T TNS_ADMIN=/u01/app/

srvctl setenv database -d LIVE -t "TNS_ADMIN=$ORACLE_HOME/network/admin,ORA_NLS10=$ORACLE_HOME/nls/data/9idata"
srvctl stop database -d LIVE
stvctl start database -d LIVE

Info about ORA_NLS10:

ORA_NLSxx is used to indicate where Oracle RDBMS/client software can locate the definitions of Charactersets (used in NLS_LANG or as NLS_CHARACTERSET/NLS_NCHAR_CHARACTERSET), NLS_SORT, NLS_LANGUAGE (or derived/related parameters) or NLS_TERRITORY (or derived/related parameters).
Those definitions are stored in .nlb files who can be found in the ORA_NLSxx directory.

When database is already created and Oracle Net connections need to be established, ORA_NLSxx is used by the listener and client software to acces the nlb file to define date/time format masks and perform characterset conversions.

For 9i and above , or do not set this so the default is used, or when explicit defining the ORA_NLSxx make sure it's set to the correct location.