Alpha Texture to Mesh problem?

Hi all,

Red circle is my problem with below link . Why some alpha can not display?

http://bc9389.awardspace.com/error.html

This is my create mesh coding. Please some body help.

//Craete Hill
hillMesh = Mesh.FromFile("Model/garden.X", MeshFlags.Managed, renderer.Device, out eMaterials);

hillTextures = new Texture[eMaterials.Length];
hillMaterials = new Material[eMaterials.Length];

for (int i = 0; i < hillMaterials.Length; i++)
{
hillMaterials = eMaterials.Material3D;
hillTextures = TextureLoader.FromFile(renderer.Device, "Images/garden.tga");
}
//======================

//Render

for (int i = 0; i < hillMaterials.Length; i++)
{
renderer.Device.Material = hillMaterials;
renderer.Device.SetTexture(0, hillTextures);
hillMesh.DrawSubset(i);
}

//==============

Best Regards,

[1397 byte] By [brian_tsim] at [2007-12-27]