Solution : https://service.sap.com/sap/support/notes/779907 (SAP Service marketplace login required)
Key words : 
database configuration              dft_prefetch_sz = automatic            tablespace configuration              alter/create tablespace, terms db2udb db6 v8fixpak2 dynpro_field_conversion dft_prefetch_sz automatic reason, configuration->database space->tablespaces, prefetchsize automatic            solution, short dump dynpro_field_conversion, database version 8 fixpak 2, dba cockpit terminate, configuration parameters, database managers, error occurs
Related Notes : 
       
| 780546 | DB6: Use of new functions in DB2 V8.2 |