Solution : https://service.sap.com/sap/support/notes/53746 (SAP Service marketplace login required)
Key words : 
informix online server software, newer informix server version, effective problem processing, newer database backend, required informix esql/, simulated production conditions, informix support group, informix development support, older database frontend, database frontend
Related Notes : 
       
| 407317 | Released operating systems for SAP kernel 6.x INFORMIX | 
| 156549 | Released operating systems for SAP kernel 4.6x INFORMIX | 
| 151546 | SAP products with Informix for the year 2000 | 
| 107410 | Database crash during workflow actions | 
| 92116 | Bug fix strategy for R/3 on Informix | 
| 85840 | Released operating systems SAP Kernel 4.0x/4.5x INFORMIX | 
| 50157 | Using recommended Informix versions | 
| 45876 | Importing new Informix Software | 
| 23872 | SAP Kernel 3.0x/3.1x INFORMIX: Released operating systems |