Sticky bit set on linux password file

While going through an annual sarbox task I noticed that on Linux (maybe unix too)
the sticky bit is set on the password file.

[oracle_at_server before]$ l $OH/dbs/orapworcl -rwSr----- 1 oracle oinstall 1536 Oct 30 2007 /u01/app/oracle/product/9.2.0/aglqa/dbs/orapworcl

The bit is shown as a capital S due to the execute bit not being set.

There's nothing in ML about it, at least I could not find anything.

The following test was performed:

shutdown database
chmod 640 orapworcl
startup database
logon to database remotely as sysdba

It doesn't appear that the SUID bit serves any purpose.

Does someone here know why the password file is SUID?

-- 
Jared Still
Certifiable Oracle DBA and Part Time Perl Evangelist

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