What is the package SYS.USER_LOCK?

Recenty I was migrating a database with a package that wouldn't compile because it couldn't find the package called upon in its code:

SQL> ALTER PACKAGE mypackage compile body; 

Warning: Package body altered with compilation errors.

SQL> show errors
Errors for PACKAGE BODY MVA3.MYPACKAGE:

PLS-00201: identifier 'USER_LOCK.SLEEP' must be declared

According to PSOUG, there are "four separate ways to induce a sleep into PL/SQL."

•dbms_backup_restore
•dbms_drs
•dbms_lock
•user_lock


PSOUG continues: "Note that USER_LOCK package is not part of the default Oracle installation"

Install as follows:

cd $ORACLE_HOME/rdbms/admin
sqlplus / as sysdba @userlock.sql