[away3d] Aw: Change UV-Data at runtime

[Guido]

if i first remove the face and than add it again in the mousemove function 
it works for 2 seconds, than an error occurs
Der Zugriff auf eine Eigenschaft oder eine Methode eines 
null-Objektverweises ist nicht möglich.
    at away3d.core.base::Geometry/findVertNormals()
    at away3d.core.base::Geometry/getVertexNormal()
    at away3d.materials.shaders::DiffusePhongShader/renderLayer()
    at away3d.materials::CompositeMaterial/renderLayer()
    at away3d.materials::CompositeMaterial/renderTriangle()
    at away3d.core.render::Renderer/renderPrimitive()
    at away3d.core.render::QuadrantTreeNode/render()
    at away3d.core.render::QuadrantRenderer/render()
    at away3d.core.session::AbstractSession/render()
    at away3d.core.session::AbstractSession/render()
    at away3d.containers::View3D/render()
    at arsani::Away3DTemplate/onEnterFrame()
    at arsani.guidotest::Away3DBasisklasse/onEnterFrame()

And it is slower.