Junk characters in email body only for specific user IDs

Question

While sending mail from SAP I am using
        SENDER = CL_SAPUSER_BCS=>CREATE( LV_SENDER_ADD ).
        CALL METHOD SEND_REQUEST->SET_SENDER
          EXPORTING
            I_SENDER = SENDER.
now while using 'User1' and 'User2'  in LV_SENDER_ADD give a perfect result.
But while using 'User3' and 'User4' in LV_SENDER_ADD sends Junk chars in the email body
ST05 Trace Results show below mention lines in red.
hh:mm:ss:ms       Type        Lasts(us)       Object                 Text                                           
19:05:07:451      CMOD          - - -         rstscb_call_back       Parameter:                                                                         
19:05:07:451      CMOD         - - -        rstswsf_was_stor      Parameter:                                                                         
19:05:07:451      CMOD              2       rstswsf_was_stor      Parameter:                          Comment:   Returncode: 0                       
19:05:07:451      CMOD              9       rstscb_call_back      Parameter:                          Comment:   Returncode: 0                       
19:05:07:451      CMOD         - - -        rscpi_init            Parameter:                                                                         
(I am converting the XSF output of Smartform  and SCP_TRANSLATE_CHARS to translate smartform output into HTML)
all the above four user have SAP_ALL authorization.
'user4' is created as a copy of 'user1'
Checking the Type CMOD says that they are call to 'C' routine 'kernal calls'
the above code is executed withe the user id of user1 2 3 4  and all of them give the same results.
when ever the sender is user1 or user2 the transmission is successful else. sends junk chars.

Answer 1

Could you tell us why/how you use SCP_TRANSLATE_CHARS?
Do theseusers have same language/country in their profile?