Edit a Wall Object (AecDbWall) in AutoCAD using VBA?

I am using AutoCAD Architectural Desktop 3.3, and I am wondering how
to edit wall objects in CAD drawings through VBA. The wall object is
created in the Architectural Desktop through the menu item
"Design/Walls/Add Wall..." .

Currently, I use the following subroutine to iterate all wall objects
in the CAD drawing. However, it seems to me that I could not change
the height of those wall objects.

Could anyone help me in this matter?

Thanks!
Jim


Sub Edit_Walls()
Dim count As Integer
count = ThisDrawing.ModelSpace.count

ReDim newObjs(count) As Object

Dim wallObj As Acad3DSolid

Dim index As Integer
For index = 0 To count - 1
Set newObjs(index) = ThisDrawing.ModelSpace.Item(index)
Debug.Print newObjs(index).ObjectID,
newObjs(index).ObjectName, newObjs(index).Handle
If StrComp(newObjs(index).ObjectName, "AecDbWall") = 0 Then
Debug.Print "This is a wall..."

newObjs(index).Color = RED
'' OK but the actual color is not changed

''newObjs(index).Height = 15
'' error here since Height is not supported

newObjs(index).Update
End If

Next



End Sub