How you put Applications 11i in Maintenance mode ?

How you put Applications 11i in Maintenance mode ?
[applmgr@srvr33 appltop]$ . APPSdb4_srvr33.env
[applmgr@srvr33 appltop]$ adadmin

 AD Administration Main Menu  --------------------------------------------------

   1.    Generate Applications Files menu

   2.    Maintain Applications Files menu

   3.    Compile/Reload Applications Database Entities menu

   4.    Maintain Applications Database Entities menu

   5.    Change Maintenance Mode

   6.    Exit AD Administration

Enter your choice [6] : 5

Change Maintenance Mode
   ----------------------------------------

Maintenance Mode is currently: [Enabled].


Maintenance mode should normally be enabled when patching
Oracle Applications and disabled when users are logged on
to the system.  See the Oracle Applications Maintenance
Utilities manual for more information about maintenance mode.


Please select an option:

   1.    Enable Maintenance Mode

   2.    Disable Maintenance Mode

   3.    Return to Main Menu

Here  internally call bellow Script
@$AD_TOP/patch/115/sql/adsetmmd.sql 

You can also put your application in maintencemode from backend :
Enable Maintenance mode :

SQL> @$AD_TOP/patch/115/sql/adsetmmd.sql ENABLE
SQL> select fnd_profile.value(‘APPS_MAINTENANCE_MODE’) from dual; –> to check

Disable Maintenance mode :

SQL> @$AD_TOP/patch/115/sql/adsetmmd.sql DISABLE
SQL> select fnd_profile.value(‘APPS_MAINTENANCE_MODE’) from dual; –> to check