Solution : https://service.sap.com/sap/support/notes/666448 (SAP Service marketplace login required)
Key words : 
sap pda companion synchronization server successfully uninstalled, pda companion applicationpda installationpda upgradeinstallation reason, pda companion application related notes---------------------------------------sp independent-------------------671038 -, sap pda companion synchronization server, pda companion truncates synchronization tables, pda companion application related notes3, symptom sap crm mobile client, pda companion installation related notes2, pda companion installation related notes---------------------------------------------4, 0 sp03-------------------sp independent-------------------664837 - registration
Related Notes : 
       
| 902083 | Unicode Collection Note for CRM 4.0 | 
| 818562 | |
| 785055 | Generic Note Released for all Mobile Client Companion Fixes | 
| 680356 | |
| 671038 | |
| 667669 | |
| 665066 | |
| 664837 | |
| 652042 | CRM Mobile Client Component: Upgrade to 4.0 SP03 | 
| 635647 | CRM Mobile Client Component: Installation/Upgrade 4.0 SP02 |