Passing parameters to exit program

I can't understand the way parameters are passing to my QIBM_QMH_REPLY_INQ exit 
program. Thera are 8 parameters:

1. BINARY(4) Type of Call
2. CHAR(20)  Qualified Message Queue Name 
3. CHAR(4)   Message Key
4. CHAR(7)   Message ID
5. CHAR(132) Reply
6. BINARY(4) Reply Length
7. BINARY(4) CCSID
8. BINARY(4) Return Action Code

I'm interested in 2nd and 3d parametres. 2nd parameter is pasiing without 
problems and i can print it with printf() and pass to other functions. 
But the 3d parameter passes as '    ' string - so it has unprintable symbols. 
I tried to write the CL exit program but the situation is the same.
With DMPCLPGM i saw the values of all these parameters. They are all have 
correct  meanings but only in hexademical representation. The string values are 
blank except the 2nd and 5th fields. 
I want to get 3d parameter in strig representation to pass it to QMHRCVM API.

Help me please.