diff --git a/package.json b/package.json
index 8708eaf..eb330a6 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
   "dependencies": {
     "babel-runtime": "^5.4.4",
     "minecraft-data": "0.7.0",
-    "minecraft-protocol": "^0.16.0",
+    "minecraft-protocol": "0.16.0",
     "mkdirp": "0.5.1",
     "moment": "^2.10.6",
     "node-dir": "~0.1.9",
diff --git a/src/lib/plugins/placeBlock.js b/src/lib/plugins/placeBlock.js
index b4da784..603a41e 100644
--- a/src/lib/plugins/placeBlock.js
+++ b/src/lib/plugins/placeBlock.js
@@ -14,7 +14,7 @@ var materialToSound = {
 module.exports.player=function(player,serv)
 {
   player._client.on("block_place",({direction,heldItem,location} = {}) => {
-    if(direction==-1 || heldItem.blockId==-1) return;
+    if(direction==-1 || heldItem.blockId==-1 || !blocks[heldItem.blockId]) return;
     var referencePosition=new Vec3(location.x,location.y,location.z);
     var directionVector=directionToVector[direction];
     var placedPosition=referencePosition.plus(directionVector);