Windows CE and the OpenDatabase method

Hi ...
I´m developing application for Windows CE on Pocket PC´s and I´m having trouble connecting to a Oracle database using the OpenDatabase method.
The problem arises when I try to create a new session to activate the OpenDatabase method. That returns an empty object.
1. This session ... is that supposed to have the same user name and password as the user is logged on in Win CE
2. The constants used to declare which to use ODBC or Jet ... does anyone know about a .bas file or .txt file with all those constants.
3. I need to let users enter a username and password. What is the best way to take that information and open a session for that user without risking a possible hacking into the system.
Pl... help ... EE