The Apps Password is stored in a flat files other than from being stored in Database.

Files which need to checked for apps password
File name:
Location of the file:  $IAS_ORACLE_HOME/Apache/modplsql/cfg/

File name: CGIcmd.dat
Location of the file : $ORACLE_HOME/reports60/server

If you are changing apps password then it would be required to change password in above files in 11i.