HRMS R12 RUP6 Patch (16000686) Failure

@/opt/R12RTI2/apps/apps_st/appl/ame/12

I'm applying patches for our RTI test instance and have got to patch 16000686.  All pre-requisites have been applied, but this patch fails with:

           FAILED: file ameeengi.pkb on worker  1.
           FAILED: file hraprvlss.pkb on worker  2.

The worker 1 log shows:

sqlplus -s APPS/***** @/opt/R12RTI2/apps/apps_st/appl/ame/12.0.0/patch/115/sql/ameeengi.pkb
Connected.
create or replace PACKAGE BODY AME_ENGINE as
*
ERROR at line 1:
ORA-04021: timeout occurred while waiting to lock object

.... and the worker 2 log shows:

sqlplus -s APPS/***** @/opt/R12RTI2/apps/apps_st/appl/per/12.0.0/patch/115/sql/hraprvlss.pkb
Connected.
CREATE OR REPLACE PACKAGE BODY HR_APPROVAL_SS AS