Solution : https://service.sap.com/sap/support/notes/494052 (SAP Service marketplace login required)
Key words : 
process hanging message bdoc types, import support package 08 crm release 3, sap service marktplatz  http, hanging bdoc type messages, incompatible bdoc type change, /crm-inst  -->sap crm 3, 'field sales upgrade guide', changed free goods tables, free goods bdoc types, synchronization bdoc type
Related Notes : 
       
| 504322 | Correction condition tables for usage free goods | 
| 497215 | |
| 497019 | |
| 494733 |