I put all the dlls and conventional sqlite4.dll SQLDrivers folder (created by me) and still did not work.

The hierarchy is as follows:

->. Exe
-> All Dll
-> Folder SQLDrivers
|---> Sqlite4.dll (nicked from the C: \ Qt \ 2009.04 \ qt \ plugins \ SQLDrivers).

Still did not work. Dar both mistake! IsValid () when no! IsOpen () (Not valid and can not open).