Unity Terrain Detail mesh toon shading

As the question infers I am trying to place terrain detail objects using unity’s terrain system, however when the terrain detail mesh has a toon shader the mesh renders without an outline or proper shading like so…

These rocks have a toon shaded material on them,
my question is, is there any way to make unity’s terrain system use toon shading for the detail meshes?

Have you tried specifying a toon shader in place of the following lines? (set towards the bottom of the FirstPassShader of the default terrain shader).

Dependency "Details0"      = "Hidden/TerrainEngine/Details/Vertexlit"
Dependency "Details1"      = "Hidden/TerrainEngine/Details/WavingDoublePass"
Dependency "Details2"      = "Hidden/TerrainEngine/Details/BillboardWavingDoublePass"
Dependency "Tree0"         = "Hidden/TerrainEngine/BillboardTree"

That, I believe, is their purpose, but having recently asked my own question concerning Shader Dependency properties and not received any replies, I’m only guessing here (there doesn’t seem to be any documentation on the subject)