Strange problem in RISC testing

I'm doing some testing on a new 270 running V4R5.  I've brought
everything over from my CISC system.  Everything I've tested (up to now)
has worked without a hitch, save for 1 program.

This program (LV27) prints vendor address labels.  Within the program I
use a procedure as follows:

        Eval     VNDNM = MixedCase(VNDNM)

to convert the name and address fields to mixed case.  When I run it, I
almost always get the following error in the job log (statements
shortened to avoid wrapping):
                                                                               
     Message . . . . :   Message  received for RPG procedure 
       LV27 (C G D F).       
     Cause . . . . . :   Message  was received by RPG procedure LV27 
       in program DILGARD/LV27 at statement
010400.                                           

Statement 010400 is one statement beyond the end of the program.  The
immediately previous message in the job log says:
                                                                               
     Message . . . . :   Function check. MCH3601 unmonitored by 
       QDBGETM at statement *N, instruction
X'0957'.                                          
     Cause . . . . . :   An escape exception message was sent to a 
       program which did not monitor for that message. The full name 
       of the program to which the unmonitored message was sent is 
       QDBGETM.  At the time the message was sent the program was 
       stopped at higher level language statement number(s) *N. If 
       more than one statement number is shown, the program was a 
       bound program.  Optimization does not allow a single statement 
       number to be determined. If *N is shown as a value, it means 
       the actual value was not available.        

The MCH3601 it is referring to is this:
                                                                              
     Message . . . . :   Pointer not set for location
referenced.                  
     Cause . . . . . :   A pointer was used, either directly or as a 
       basing pointer, that has not been set to an
address.                               

                                                                              
Now for the strange part(s):

1) If I run the program in debug mode, it works fine.  Every time.

2) If I comment out the "MixedCase" procedure statements, it runs fine
irrespective of debug mode.

3) Once in a great while, the program will run partially through the
name & address file before bombing.  I am assuming that it has something
to do with the MixedCase procedure, but I've used it for at least a
couple of years on CISC with nary a problem.  And I use it in various
programs, all of which work OK except for this one.

I have downloaded and applied every RPG PTF available.  I was on the
latest group PTFs but noticed there are new group PTFs available just
last week for Database, Hipers, Backup Recovery Solutions, and HTTP
server, so I have all of those ordered.

Any help is appreciated.  Thanks.  I'm going to try debugging the
program containing the procedure next.

-- 
-Jeff
The opinions expressed are my own and not necessarily 
the opinion of my company.  Unless I say so.
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