"Unable to compile effect" error

Hi everybody!

I get the following errors (relevant excerpt) in the console:

BJS - [13:19:53]: Unable to compile effect:...

...

BJS - [13:19:53]: Error: ERROR: 0:1001: 'vBumpInfos' : undeclared identifier
ERROR: 0:1001: 'y' :  field selection requires structure or vector on left hand side

meanwhile trying to add a normal map (by means of bump texture) to any PBR Material.

My material definition is:

var myMaterial=new BABYLON.PBRMaterial("plastic",Scene);
myMaterial.reflectionTexture=txtHDR;
myMaterial.bumpTexture=new BABYLON.Texture("assets/textures/11_onetile.png",Scene);                                        
myMaterial.cameraExposure=exposure;
myMaterial.cameraContrast=contrast;
myMaterial.microSurface=0.96;
myMaterial.albedoColor=BABYLON.Color3.White();
myMaterial.albedoTexture=new BABYLON.Texture("assets/textures/QIS_Exterior_BaseColor.png",Scene);
myMaterial.reflectivityColor=new BABYLON.Color3(0.07,0.07,0.07);
myMaterial.metallicTexture=new BABYLON.Texture("assets/textures/QIS_Exterior_Metallic_PBR.png",Scene);
myMaterial.useRoughnessFromMetallicTextureAlpha=false;
myMaterial.useRoughnessFromMetallicTextureGreen=true;

If I remove the offending line: myMaterial.bumpTexture=new BABYLON.Texture("assets/textures/11_onetile.png",Scene); the material works flawless (but of course without normal map).

My question:

Are BJS PBR Materials compatible with Normal Maps?