primary and secondary files, match fields, summarizing/printing s ingle line per key

Mabuhay RPG gurus!

A colleague has this problem, which I cannot solve, involving primary and
secondary files and match fields. Here are the relevant code fragments and a
sample output. A record pertaining to a particular key doesn't necessarily
have to be in both files.

SAMPLE PROGRAM
==============
IPLNMJ1      01                                        
I                                              PLOYER  M6
I                                              PLOMKTL3M5
I                                              PLOIGRL2M4
I                                              PLOCSZL1M3
I                                              PLOCVTL1M2
I                                              PLOITML1M1
IINVSUM      02                                        
I                                              IVSYER  M6
I                                              IVSMKTL3M5
I                                              IVSIGRL2M4
I                                              IVSCSZL1M3
I                                              IVSCVTL1M2
I                                              IVSITML1M1
----------
  MAIN
----------
.
.
.
CL1                   EXSR PRTDTL
.
.


SAMPLE OUTPUT
=============
                                                          Cur Mo.   Total 
     Item_  Size__  Variety___  Market_PO_Description____  ___PO__  Shipmts
  CONC FOR DC OR DIRECT                                                    
*1*  01160  12-46   PO          EUROPE MARKET                1,000

*1*  01160  12-46   PO          EUROPE MARKET                           204

*2*  01254  6-10    J-          EUROPE MARKET                1,000         
*2*  01254  6-10    J-          EUROPE MARKET                           272

                                Sub-total                    2,000      476


QUESTION
========
*INL1 controls the printing of a detail line. In the sample output above,
lines indicated by *1* should supposedly appear in one line, lines indicated
by *2* also in one line. However, as you can see, *INL1 is triggered twice,
one for each file (primary and secondary), so that they were printed on two
separate lines. Printing on every other setting of *INL1 also doesn't work
because the records pertaining to a particular key need not appear in both
files.

Does anybody here knows of a technique that will print the summary of a
record with details coming from two separate files in a single line? We are
using RPG/400 on V4R5M0 (by order of our BDFL).

Thanks in advance.

--
Carl Mañoso
"It is not real work unless you would rather be doing something else."
[J.M.BARRIE]