diff --git a/core/src/main/scala/spark/Executor.scala b/core/src/main/scala/spark/Executor.scala
index f32e66bef471dcbe3be2ebf0b08e204660eb005a..7764acad1acc27492961c4832476b3124b9b32d2 100644
--- a/core/src/main/scala/spark/Executor.scala
+++ b/core/src/main/scala/spark/Executor.scala
@@ -108,7 +108,7 @@ class Executor extends mesos.Executor with Logging {
       loader = {
         try {
           val klass = Class.forName("spark.repl.ExecutorClassLoader").asInstanceOf[Class[_ <: ClassLoader]]
-          val constructor = klass.getConstructor(classUri.getClass, loader.getClass)
+          val constructor = klass.getConstructor(classOf[String], classOf[ClassLoader])
           constructor.newInstance(classUri, loader)
         } catch {
           case _: ClassNotFoundException => loader
diff --git a/core/src/main/scala/spark/HadoopFile.scala b/core/src/main/scala/spark/HadoopFile.scala
index 0a7996c7bdcc708ddc49ba41919c65ba2ba05a37..beb53ce1a54338be2cedef755eea9da9b1b522e7 100644
--- a/core/src/main/scala/spark/HadoopFile.scala
+++ b/core/src/main/scala/spark/HadoopFile.scala
@@ -3,6 +3,7 @@ package spark
 import mesos.SlaveOffer
 
 import org.apache.hadoop.io.LongWritable
+import org.apache.hadoop.io.NullWritable
 import org.apache.hadoop.io.Text
 import org.apache.hadoop.mapred.FileInputFormat
 import org.apache.hadoop.mapred.InputFormat
@@ -51,6 +52,15 @@ extends RDD[(K, V)](sc) {
                    .asInstanceOf[InputFormat[K, V]]
   }
 
+  // Helper method for creating a Hadoop Writable, because the commonly used
+  // NullWritable class has no constructor
+  def createWritable[T](clazz: Class[T]): T = {
+    if (clazz == classOf[NullWritable])
+      NullWritable.get().asInstanceOf[T]
+    else
+      clazz.newInstance()
+  }
+
   override def splits = splits_
 
   override def compute(theSplit: Split) = new Iterator[(K, V)] {
@@ -63,8 +73,8 @@ extends RDD[(K, V)](sc) {
     val fmt = createInputFormat(conf)
     reader = fmt.getRecordReader(split.inputSplit.value, conf, Reporter.NULL)
 
-    val key: K = keyClass.newInstance()
-    val value: V = valueClass.newInstance()
+    val key: K = createWritable(keyClass)
+    val value: V = createWritable(valueClass)
     var gotNext = false
     var finished = false
 
diff --git a/project/build/SparkProject.scala b/project/build/SparkProject.scala
index 7ebd92fde6836c6a20f51d3385732cc94cea3a3b..f33b42b986836c60b6fa26aebaadc9149a7856a4 100644
--- a/project/build/SparkProject.scala
+++ b/project/build/SparkProject.scala
@@ -16,10 +16,11 @@ class SparkProject(info: ProjectInfo) extends ParentProject(info) with IdeaProje
 
   lazy val bagel = project("bagel", "Bagel", new BagelProject(_), core)
 
-  lazy val jettyWebapp = "org.eclipse.jetty" % "jetty-webapp" % "7.4.1.v20110513" % "provided"
-
   trait BaseProject extends BasicScalaProject with ScalaPaths with BasicPackagePaths with Eclipsify with IdeaProject {
     override def compileOptions = super.compileOptions ++ Seq(Unchecked)
+
+    lazy val jettyServer = "org.eclipse.jetty" % "jetty-server" % "7.4.2.v20110526"
+    
     override def packageDocsJar = defaultJarPath("-javadoc.jar")
     override def packageSrcJar= defaultJarPath("-sources.jar")
     lazy val sourceArtifact = Artifact.sources(artifactID)
@@ -38,21 +39,16 @@ class SparkProject(info: ProjectInfo) extends ParentProject(info) with IdeaProje
     val asm = "asm" % "asm-all" % "3.3.1"
     val scalaTest = "org.scalatest" % "scalatest_2.9.0" % "1.4.1" % "test"
     val scalaCheck = "org.scala-tools.testing" % "scalacheck_2.9.0" % "1.8" % "test"
-    val jetty = jettyWebapp
   }
 
-  class ReplProject(info: ProjectInfo) extends DefaultProject(info) with BaseProject with DepJar with XmlTestReport {
-    val jetty = jettyWebapp
-  }
+  class ReplProject(info: ProjectInfo) extends DefaultProject(info) with BaseProject with DepJar with XmlTestReport
 
   class ExamplesProject(info: ProjectInfo) extends DefaultProject(info) with BaseProject {
     val colt = "colt" % "colt" % "1.2.0"
   }
 
-  class BagelProject(info: ProjectInfo) extends DefaultProject(info) with BaseProject with DepJar with XmlTestReport {
-    val jetty = jettyWebapp
-  }
-	
+  class BagelProject(info: ProjectInfo) extends DefaultProject(info) with BaseProject with DepJar with XmlTestReport
+
 }