Can we override the QRNXMSG message file for a certain job?

When a certain job runs, we want to change the RNQ1218 message in
QRNXMSG in QSYS to give the users only the option to C(ancel).  We do
not want to add automatic replies, since we want to let the customer
cancel and be aware that the job was cancelled.

We have created another message file(RNXMSGF) with just that one
message id with the only valid value as C and have performed an
override to QRNXMSG using the OVRMSGF command.

When the job fails on a record lock condition, it still displays the
message from the QRNXMSG rather than the message file it was overriden
to in the initial CL program.

The couple of questions i have are
- Can the QRNXMSG be overriden ? Is what we are trying to do even feasible.
- What are the other options available to change the message id only
for the job to just allow for the cancel.

I have put a MONITOR around the scenarios we know can fail and are
capturing the error status code 1218 and doing some error handling,
but this is the solution we want to implement for the other chain
scenarios that could produce a record lock that we have not yet put a
MONITOR around.

Original message id
 Message ID . . . . . . . . . :   RNQ1218
 Message file . . . . . . . . :   QRNXMSG
   Library  . . . . . . . . . :     QSYS
 Message text . . . . . . . . :   Unable to allocate a record in file
&7 (R C G D F).

Changed message id
 Message ID . . . . . . . . . :   RNQ1218
 Message file . . . . . . . . :   RNXMSGF
   Library  . . . . . . . . . :     TSTLIB
 Message text . . . . . . . . :   Unable to allocate a record in file
&7 (C)

Thanks

Krish Thirumalai