Solution : https://service.sap.com/sap/support/notes/584926 (SAP Service marketplace login required)
Summary : 
      This SAP note addresses an error identified by the runtime exception RAISE_EXCEPTION with the specific condition "QOUT_QIN_MODE_MISMATCH" occurring within the ARFC_INIT module. This issue arises when qRFCs with conflicting modes are invoked in the same LUW, due to improper resetting of QINFLAG after inbound queue processing. The solution provided involves updating to qRFC Version 6.20.45 Supplement 11 or higher, which properly handles the flag reset and prevents the error. Users must verify their current qRFC version via Transaction SMQS before importing the update based on the guidelines stipulated in Notes 481278 and 438015.
Key words : 
runtime error raise_exception  exception condition, transaction smqs --> info --> version, arfctidcnt = tid-arfctidcnt, %_reserv = chk_state-arfcreserv, %_reserv-qrfcflag = qf_qin, terms qout_qin_mode_mismatch reason, aforementioned short dump, lower qrfc version, additional qrfc calls, incorrect application programming
Related Notes : 
       
| 634869 | SAPKU40001: Support Package 01 for CRM 4.0 | 
| 628397 | SAPKU30015: Support Package 15 for EBP 3.0/CRM 3.0 | 
| 601721 | Supplement 11 for qRFC in 3.x,4.x, 6.10, 6.20 and 6.40 | 
| 481278 | Installing qRFC Version 6.20.045 | 
| 438015 | Latest qRFC version and supplement for 3.x, 4.x, 6.10, 6.20 |