I have this code to generate a report from c# in windows forms

HTML Code:
ReportDocument prueba =new ReportDocument();
try 
{
	prueba.Load(@"..\..\prueba.rpt");
	CrystalDecisions.Shared.TableLogOnInfo tliCurrent;	
      foreach(CrystalDecisions.CrystalReports.Engine.Table tbCurrent in prueba.Database.Tables)
      {
	tliCurrent = tbCurrent.LogOnInfo;					tliCurrent.ConnectionInfo.ServerName = "server";			tliCurrent.ConnectionInfo.UserID = vclave; 				tliCurrent.ConnectionInfo.Password = vclave; 				tliCurrent.ConnectionInfo.DatabaseName = vdb;
	tbCurrent.ApplyLogOnInfo(tliCurrent);
       }
	crvBasic.ReportSource = prueba;
	crvBasic.Zoom(2);} 
	catch( LoadSaveReportException Exp )
            { 
	MessageBox.Show("No se encuentra la ruta y/o el reporte para ser ejecutado.", "Load Report Error");} 
	catch( Exception Exp)
	{
   	 MessageBox.Show(Exp.Message, "General Error");}
The problem is:
if the report use a table in oracle, then the app ask me to type servername,password, etc and finally does not work.
But if i only change to a report using SQL SERVER without changing anything: IT WORKS!!!!

Any help?