adjustment layer: solid fill

Hi I'm looking for a way to create an adjustment layer kind :"solid fill"  with applescipt.

It should have a fill with an Lab color (eg; L= 20, a=10, b=13)

Code:

   tellapplication "Adobe Photoshop CS3"

       tellcurrent document

          setnewLayer to makeart layerwith properties {name:"MyInkName", kind:solid fill layer, color:{class:Lab color, value_L:20, value_a:10, value_b:13}}

         endtell

  endtell

error:

You can only change the layer's kind to text or normal.

Thanks,

Koen