Cannot read property 'layertype' of undefined

[Revo86]

Hello,

we have multiple layers in one theme embedded like this:

{"name": "Stadtplanung",
"layers": [
            {"name":    
                "rp_bebauue_i,bauleitplanung_BP,Themenkarten_Bebauungsplan_RVR_Bebauungsplaene",
                     "layers": []
        }]}

If one opens a permalink like : http://xyz.example.com?activeLayers=rp_bebauue_i,bauleitplanung_BP,Themenkarten_Bebauungsplan_RVR_Bebauungsplaene

none of these layers gets automatically switched on and in console the error is thrown:
Cannot read property 'layertype' of undefined

debugging points towards gui.js with the line

var permaLayerType = Map.layers[permaLayer].layertype;

Any ideas on how to fix this? This error is not thrown, if a single theme permalink is used.