code: public void clearProblemMarkers()
  	{
  		try
  		{
  			this.project.deleteMarkers(IMarker.PROBLEM, true, IResource.DEPTH_INFINITE);
  
  		} catch (CoreException e)
  		{
  			if (VdmCore.DEBUG)
  			{
  				VdmCore.log("VdmProject clearProblemMarkers", e);
  			}
  		}
  
  	}
docs: *
  This method removed all problem markers and its sub-types from the project. It is called before an instance of
  the AbstractBuilder is created
  
  @param project
  The project which should be build.