Solution : https://service.sap.com/sap/support/notes/1138550 (SAP Service marketplace login required)
Key words : 
\usr\sap\<sid>\sys\global\db6\ <os>\db6_clidriver\, path <inst-drive>\ese\image, 5 luw cli/jdbc driver dvd, db2 drop table systools, db2 remote command service, bat -uthe script 'db6_update_client, directory global/db6, relevant windows operating system, fixpakwindows 2003upgrade systools, sap service marketplace
Related Notes : 
       
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| 1138549 | DB6: Installation of Fix Packs for DB2 V9.5 (UNIX & Linux) | 
| 1089578 | DB6: Using DB2 Version 9.5 with SAP Software | 
| 1086130 | DB6: DB2 9.5 Standard Parameter Settings | 
| 816773 | DB6: Installing an SAP OEM license |