Apache storm error when submitting topology locally

Im trying to submit my Storm topology locally however I keep receiving this error on the console when calling cluster.submitTopology():

[Thread-5] ERROR backtype.storm.event - Error when processing event java.lang.IllegalStateException: Attempting to call unbound fn: 'http://ift.tt/1BA4LEk?

[Thread-5] ERROR backtype.storm.util - Halting process: ("Error when processing an event")

public static void main(String[] args) throws Exception {

TopologyBuilder builder = new TopologyBuilder();

builder.setSpout("twitterspout", new TwitterSpout());
builder.setBolt("sentiment", new SentimentBolt()).shuffleGrouping("twitterspout");
builder.setBolt("dimension", new DimensionBolt()).shuffleGrouping("twitterspout");
builder.setBolt("clustering", new ClusteringBolt())
.fieldsGrouping("dimension", new Fields("dimension"))
.fieldsGrouping("sentiment", new Fields("sentiment"));

Config conf = new Config();
conf.setDebug(true);


System.out.print("Creating local Cluster...");
LocalCluster cluster = new LocalCluster();
System.out.println("Done!");

cluster.submitTopology("enrichment", conf, builder.createTopology());

}

Any help appreciated.