QSH with variable vs hard coding

Hello all!

I have a CL program that executes the following
QSH CMD('jar -cfM /JOHN/TESTZIP1.ZIP /JOHN/TESTZIP1.PDF')
and it works fine.

I changed the CL to remove the hard coded file names:

DCL VAR(&PDFFILE) TYPE(*CHAR) LEN(50) VALUE('/JOHN/TESTZIP1.PDF')
DCL VAR(&ZIPFILE) TYPE(*CHAR) LEN(50) VALUE('/JOHN/TESTZIP1.ZIP')
DCL VAR(&CMD)     TYPE(*CHAR) LEN(256)
DCL VAR(&SQUOTE)  TYPE(*CHAR) LEN(1) value('''')   

CHGVAR     VAR(&CMD) VALUE(&SQUOTE *TCAT 'jar -cfM' *BCAT &ZIPFILE *BCAT
&PDFFILE *TCAT &SQUOTE)
                                   
QSH        CMD(&CMD)

ENDPGM

In debug the variable &CMD shows a value of 
'jar -cfM /JOHN/TESTZIP1.ZIP /JOHN/TESTZIP1.PDF'
(includes the singles quotes)

But this method fails with message
qsh: 001-0014 Command jar -cfM /JOHN/TESTZIP1.ZIP /JOHN/TESTZIP1.PDF not
found.                                                             

These test are being run interactively, I can't seem to see a difference
between the two.

Anyone have any suggestions?

John