You can use vertex adjust eg
private function morphIt(fromM:Mesh, tooM:Mesh):void
{
//should have a check to make sure both mesh have equal vertices
for (var i:int = 0; i < fromM.geometry.vertices.length; i++)
{
fromM.geometry.vertices[i].adjust(tooM.geometry.vertices[i].x,
tooM.geometry.vertices[i].y, tooM.geometry.vertices[i].z ,0.1)
}
}
