exp for OS/390

[Rockinw311]

I'm trying to set up a job that will do an exp on MVS connecting to an AIX box running Oracle 10g. After doing some searching, I was only able to find one example script at

http://orafaq.com/scripts/mvs/export.txt

When I run the test job I created, I'm consistently getting the following error:
Export: Release 10.2.0.3.0 - Production on Monday, 18 June, 2007 14:14:33
Copyright (c) 2003, 2005, Oracle. All rights reserved.
Username:
UDE-00008: operation generated ORACLE error 12545
ORA-12545: Connect failed because target host or object does not exist
.STEPS01 .SYSERR 9

I've tried pretty much everything I can think of, switching member based parfiles to inline in the JCL, switching from tape to disk for the out file, changing the DCB for the out file, removing all members I could, attempting to create an ORA$ENV member, etc.. The version I'm currently working with looks like the following:

//DN8747OE JOB (1MDB,CPSC,03,5),'ORACLE EXP',
// SCHENV=HA00,NOTIFY=&SYSUID
//***************************************************************
//JOBLIB DD DSN=SUPT.ORACLE.SERVER.CMDLOAD,DISP=SHR
// DD DSN=SUPT.ORACLE.SERVER.MESG,DISP=SHR
//***************************************************************
//STEPS01 EXEC PGM=EXP <--- have tried this one and EXPDP
//SYSMDUMP DD SYSOUT=*
//SYSOUT DD SYSOUT=*,DCB=(LRECL=132,BLKSIZE=1320,RECFM=VB)
//SYSERR DD SYSOUT=*,DCB=(LRECL=132,BLKSIZE=1320,RECFM=VB)
//ORAPRINT DD SYSOUT=*
//*RA$ENV DD DSN=DN8747.ORACLE.TEST.CNTLCARD(ORAENV),DISP=SHR
//ARCDATA DD DSN=DN8747.ORA.EXPTST.A070618,
// UNIT=3590TAPE,VOL=(,RETAIN,,99),
// DCB=(PSDSCB,RECFM=FB,BLKSIZE=32760),
// DISP=(NEW,CATLG,DELETE),
// RETPD=2000
//TNSNAMES DD DSN=MDNCNSA.CNTLLIB(TNSNAMES),DISP=SHR
//SYSIN DD DSN=DN8747.ORACLE.TEST.CNTLCARD(MDNCNPF),DISP=SHR

Where arcdata is the tape file I'm trying to write out to from the exp.
MDNCNPF contains the following:
USERID=userid/password <--- have tried this both with and without the @SID usually used with "exp username/password@SID"
FILE=/DD/ARCDATA
CONSISTENT=Y
DIRECT=Y
BUFFER=9999999
COMPRESS=Y
ROWS=Y
CONSTRAINTS=Y
GRANTS=Y
INDEXES=Y
TRIGGERS=Y
TABLES=(STATE_NAME_LOOKUP)

The TNSNAMES member works with the SQLPlus and Loader jobs we have using it. I've tried moving the parfile info to be inline, like the example had (below), but no luck. Any ideas where the problem may be coming in?

//PARFILE DD *
USERID=USERNAME/PASSWORD
FILE=/DD/ARCDATA
CONSISTENT=Y
DIRECT=Y
BUFFER=9999999
...