Bitblt

Hello all,
did anyone have success in using bitblt under ce6?
Im developing with vb2005, and cant get it to work... I'm using the same
that works under desktop software.

the code is

    Public Sub WriteBuffer(ByRef g As str_g, ByRef b As str_g, ByVal
posicion As Point, ByVal tam As Size)
        Dim dc1 As IntPtr = b.g.GetHdc
        Dim old1 As IntPtr = SelectObject(dc1, b.hb)

        Dim lDC As IntPtr = g.g.GetHdc
        Dim hOld As IntPtr = SelectObject(lDC, g.hb)

        BitBlt(dc1, posicion.X, posicion.Y, tam.Width, tam.Height, lDC,
posicion.X, posicion.Y, RasterOps.SRCCOPY)

        SelectObject(lDC, hOld)
        g.g.ReleaseHdc(lDC)

        SelectObject(dc1, old1)
        b.g.ReleaseHdc(dc1)
    End Sub

if I use the graphics.drawimage it works fine (and slow), but with bitblt
it is just black.

thanks!