I found wierd thing:
When creating plane:
var plaGeo:PlaneGeometry = new PlaneGeometry(width,width,1,1,true,true);
plane = new Mesh(plaGeo,“some mat”);
And add it to another object, merge throw this error:
RangeError: Error #1125: The index 8 is out of range 8.
at away3d.tools.commands::Merge/merge()[\away3d-away3d-core-fp11-v4.0.0-beta-508-g8f6e673\away3d-away3d-core-fp11-8f6e673\src\away3d\tools\commands\Merge.as:363]
at away3d.tools.commands::Merge/applyToContainer()[\away3d-away3d-core-fp11-v4.0.0-beta-508-g8f6e673\away3d-away3d-core-fp11-8f6e673\src\away3d\tools\commands\Merge.as:96]
But when I make planeGeometry with dubleSided = false
every think is ok.