Printing a V2d_View

I'm using WinNT and OpenCascade Ver. 4.0.
I want to print the View (V2dView), however i get compiler errors when i try to create a WNT_DDriver object.
(The Function DrawTextA(..) is only virtual not implemented)

When I correct the compiler error by implementing the function in a class WNT_DDriverEx, everything seems to be OK, but when i plot the view the programm crashes.

Where is my fault?

My code looks like this:

Handle_WNT_DDriver myPrintDriver = new WNT_DDriver(cPrnName, "spool.emf", WNT_OT_PORTRAIT, 1.0, 1);

m_OC4Ctrl->View2D()->PlotScreen(myPrintDriver);