diff --git a/launch/src/test/scala/EnumerationTest.scala b/launch/src/test/scala/EnumerationTest.scala
index 8fcc540cd..c880fd935 100644
--- a/launch/src/test/scala/EnumerationTest.scala
+++ b/launch/src/test/scala/EnumerationTest.scala
@@ -29,7 +29,7 @@ object EnumerationTest extends Properties("Enumeration")
 	{
 		def invalid(s: String) =
 			("valueOf(" + s + ")") |:
-				Prop.throws(enum.toValue(s), classOf[Exception])
+				Prop.throws(classOf[Exception])(enum.toValue(s))
 		def valid(s: String, expected: Enumeration#Value) =
 			("valueOf(" + s + ")") |:
 			("Expected " + expected) |:
diff --git a/launch/src/test/scala/ListMapTest.scala b/launch/src/test/scala/ListMapTest.scala
index 53ea7252c..9bc3d8219 100644
--- a/launch/src/test/scala/ListMapTest.scala
+++ b/launch/src/test/scala/ListMapTest.scala
@@ -16,12 +16,12 @@ object ListMapProperties extends Properties("ListMap")
 		{ (map + (key, value) ).get(key)  == Some(value) }
 	}
 	property("remove") = Prop.forAll { (map: ListMap[Int,Int], key: Int) =>
-		{ Prop.throws((map - key)(key), classOf[Exception]) } &&
+		{ Prop.throws(classOf[Exception])((map - key)(key)) } &&
 		{ !(map - key).contains(key) } &&
 		{ (map - key).get(key).isEmpty }
 	}
 	property("empty") = Prop.forAll { (key: Int) =>
-		{ Prop.throws(ListMap.empty(key), classOf[Exception]) }
+		{ Prop.throws(classOf[Exception])(ListMap.empty(key)) }
 		{ !ListMap.empty.contains(key) } &&
 		{ ListMap.empty.get(key).isEmpty }
 	}
diff --git a/launch/src/test/scala/PreTest.scala b/launch/src/test/scala/PreTest.scala
index ddbcb6e24..baf486a91 100644
--- a/launch/src/test/scala/PreTest.scala
+++ b/launch/src/test/scala/PreTest.scala
@@ -10,12 +10,12 @@ object PreTest extends Properties("Pre")
 	property("isEmpty") = Prop.forAll( (s: String) => (s.isEmpty == isEmpty(s)) )
 	property("isNonEmpty") = Prop.forAll( (s: String) => (isEmpty(s) != isNonEmpty(s)) )
 	property("assert true") = { assert(true); true }
-	property("assert false") = Prop.throws(assert(false), classOf[AssertionError])
+	property("assert false") = Prop.throws(classOf[AssertionError])(assert(false))
 	property("assert true with message") = Prop.forAll { (s: String) => assert(true, s); true }
-	property("assert false with message") = Prop.forAll( (s: String) => Prop.throws(assert(false, s), classOf[AssertionError] ) )
-	property("require false") = Prop.forAll( (s: String) => Prop.throws(require(false, s), classOf[IllegalArgumentException]) )
+	property("assert false with message") = Prop.forAll( (s: String) => Prop.throws(classOf[AssertionError] )(assert(false, s)) )
+	property("require false") = Prop.forAll( (s: String) => Prop.throws(classOf[IllegalArgumentException])(require(false, s)) )
 	property("require true") = Prop.forAll { (s: String) => require(true, s); true }
-	property("error") = Prop.forAll( (s: String) => Prop.throws(error(s), classOf[BootException]) )
+	property("error") = Prop.forAll( (s: String) => Prop.throws(classOf[BootException])(error(s)) )
 	property("toBoolean") = Prop.forAll( (s: String) => trap(toBoolean(s)) == trap(java.lang.Boolean.parseBoolean(s)) )
 	property("toArray") = Prop.forAll( (list: List[Int]) => arrEquals(list.toArray, toArray(list)) )
 	property("toArray") = Prop.forAll( (list: List[String]) => objArrEquals(list.toArray, toArray(list)) )
diff --git a/main/actions/src/test/scala/sbt/compiler/EvalTest.scala b/main/actions/src/test/scala/sbt/compiler/EvalTest.scala
index 1cff2f635..62ed31ccf 100644
--- a/main/actions/src/test/scala/sbt/compiler/EvalTest.scala
+++ b/main/actions/src/test/scala/sbt/compiler/EvalTest.scala
@@ -11,7 +11,7 @@ object EvalTest extends Properties("eval")
 	private[this] val reporter = new StoreReporter
 	import reporter.{ERROR,Info,Severity}
 	private[this] val eval = new Eval(_ => reporter, None)
-	
+
 	property("inferred integer") = forAll{ (i: Int) =>
 		val result = eval.eval(i.toString)
 		(label("Value", value(result)) |: (value(result) == i)) &&
@@ -25,11 +25,11 @@ object EvalTest extends Properties("eval")
 		(label("Type", result.tpe) |: (result.tpe == IntType)) &&
 		(label("Files", result.generated) |: (result.generated.isEmpty))
 	}
-	
+
 	property("type mismatch") = forAll{ (i: Int, l: Int) =>
 		val line = math.abs(l)
 		val src = "mismatch"
-		throws(eval.eval(i.toString, tpeName =Some(BooleanType), line = line, srcName = src), classOf[RuntimeException]) &&
+		throws(classOf[RuntimeException])(eval.eval(i.toString, tpeName =Some(BooleanType), line = line, srcName = src)) &&
 		hasErrors(line+1, src)
 	}
 
diff --git a/main/src/test/scala/TestBuild.scala b/main/src/test/scala/TestBuild.scala
index cd852086d..ac67e98a8 100644
--- a/main/src/test/scala/TestBuild.scala
+++ b/main/src/test/scala/TestBuild.scala
@@ -22,7 +22,7 @@ object TestBuild
 	val MaxIDSize = 8
 	val MaxDeps = 8
 	val KeysPerEnv = 10
-	
+
 	val MaxTasksGen = chooseShrinkable(1, MaxTasks)
 	val MaxProjectsGen = chooseShrinkable(1, MaxProjects)
 	val MaxConfigsGen = chooseShrinkable(1, MaxConfigs)
@@ -53,7 +53,7 @@ object TestBuild
 					(Scope.display(scope, "<key>"), showKeys(map))
 			scopeStrings.toSeq.sorted.map(t => t._1 + t._2).mkString("\n\t")
 		}
-		val extra: BuildUtil[Proj] = 
+		val extra: BuildUtil[Proj] =
 		{
 			val getp = (build: URI, project: String) => env.buildMap(build).projectMap(project)
 			new BuildUtil(keyIndex, data, env.root.uri, env.rootProject, getp, _.configurations.map(c => ConfigKey(c.name)), Relation.empty)
@@ -148,7 +148,7 @@ object TestBuild
 	}
 	final class Taskk(val key: AttributeKey[String], val delegates: Seq[Taskk])
 	{
-		override def toString = key.label + " (delegates: " + delegates.map(_.key.label).mkString(", ")  + ")"	
+		override def toString = key.label + " (delegates: " + delegates.map(_.key.label).mkString(", ")  + ")"
 	}
 
 	def mapBy[K, T](s: Seq[T])(f: T => K): Map[K, T] = s map { t => (f(t), t) } toMap;
@@ -214,7 +214,7 @@ object TestBuild
 	implicit def envGen(implicit bGen: Gen[Build], tasks: Gen[Seq[Taskk]]): Gen[Env] =
 		for(i <- MaxBuildsGen; bs <- listOfN(i, bGen); ts <- tasks) yield new Env(bs, ts)
 	implicit def buildGen(implicit uGen: Gen[URI], pGen: URI => Gen[Seq[Proj]]): Gen[Build] = for(u <- uGen; ps <- pGen(u)) yield new Build(u, ps)
-	
+
 	def nGen[T](igen: Gen[Int])(implicit g: Gen[T]): Gen[List[T]] = igen flatMap { ig => listOfN(ig, g) }
 
 	implicit def genProjects(build: URI)(implicit genID: Gen[String], maxDeps: Gen[Int], count: Gen[Int], confs: Gen[Seq[Config]]): Gen[Seq[Proj]] =
@@ -262,8 +262,8 @@ object TestBuild
 				val next = for(depCount <- maxDeps; d <- pick(depCount min xs.size, xs) ) yield (x, d.toList)
 				genAcyclic(maxDeps, xs, next :: acc)
 		}
-	def sequence[T](gs: Seq[Gen[T]]): Gen[Seq[T]] = Gen { prms =>
- 		Some(gs map { g => g(prms) getOrElse error("failed generator") })
+	def sequence[T](gs: Seq[Gen[T]]): Gen[Seq[T]] = Gen.parameterized { prms =>
+		wrap( gs map { g => g(prms) getOrElse error("failed generator") } )
 	}
 	type Inputs[A,T] = (T, Seq[T], Seq[A] => A)
 }
diff --git a/project/Util.scala b/project/Util.scala
index 4ffe70876..cedfe1e40 100644
--- a/project/Util.scala
+++ b/project/Util.scala
@@ -37,7 +37,7 @@ object Util
 	def minProject(path: File, nameString: String) = Project(normalize(nameString), path) settings( commonSettings(nameString) ++ publishPomSettings : _* )
 	def baseProject(path: File, nameString: String) = minProject(path, nameString) settings( base : _*)
 	def testedBaseProject(path: File, nameString: String) = baseProject(path, nameString) settings(testDependencies)
-	
+
 	lazy val javaOnly = Seq[Setting[_]](/*crossPaths := false, */compileOrder := CompileOrder.JavaThenScala, unmanagedSourceDirectories in Compile <<= Seq(javaSource in Compile).join)
 	lazy val base: Seq[Setting[_]] = Seq(projectComponent) ++ baseScalacOptions ++ Licensed.settings
 	lazy val baseScalacOptions = Seq(
@@ -47,10 +47,10 @@ object Util
 			case _ => Seq("-feature", "-language:implicitConversions", "-language:postfixOps", "-language:higherKinds", "-language:existentials")
 		}
 	)
-	
+
 	def testDependencies = libraryDependencies <++= includeTestDependencies { incl =>
 		if(incl) Seq(
-			"org.scalacheck" %% "scalacheck" % "1.10.0" % "test",
+			"org.scalacheck" %% "scalacheck" % "1.11.0" % "test",
 			"org.specs2" %% "specs2" % "1.12.3" % "test",
 			"junit" % "junit" % "4.11" % "test"
 		)
@@ -59,7 +59,7 @@ object Util
 
 	lazy val minimalSettings: Seq[Setting[_]] = Defaults.paths ++ Seq[Setting[_]](crossTarget := target.value, name <<= thisProject(_.id))
 
-	def projectComponent = projectID <<= (projectID, componentID) { (pid, cid) => 
+	def projectComponent = projectID <<= (projectID, componentID) { (pid, cid) =>
 		cid match { case Some(id) => pid extra("e:component" -> id); case None => pid }
 	}
 
@@ -148,7 +148,7 @@ object Util
 		val init = keywords.map(tn => '"' + tn + '"').mkString("Set(", ", ", ")")
 		val ObjectName = "ScalaKeywords"
 		val PackageName = "sbt"
-		val keywordsSrc = 
+		val keywordsSrc =
 """package %s
 object %s {
 	val values = %s
@@ -188,7 +188,7 @@ object Licensed
 	lazy val seeRegex = """\(see (.*?)\)""".r
 	def licensePath(base: File, str: String): File = { val path = base / str; if(path.exists) path else error("Referenced license '" + str + "' not found at " + path) }
 	def seePaths(base: File, noticeString: String): Seq[File] = seeRegex.findAllIn(noticeString).matchData.map(d => licensePath(base, d.group(1))).toList
-	
+
 	def settings: Seq[Setting[_]] = Seq(
 		notice <<= baseDirectory(_ / "NOTICE"),
 		unmanagedResources in Compile <++= (notice, extractLicenses) map { _ +: _ },
diff --git a/util/collection/src/test/scala/DagSpecification.scala b/util/collection/src/test/scala/DagSpecification.scala
index 7cf19f2df..77ff80120 100644
--- a/util/collection/src/test/scala/DagSpecification.scala
+++ b/util/collection/src/test/scala/DagSpecification.scala
@@ -18,7 +18,7 @@ object DagSpecification extends Properties("Dag")
 	private def dagGen(nodeCount: Int): Gen[TestDag] =
 	{
 		val nodes = new HashSet[TestDag]
-		def nonterminalGen(p: Gen.Params): Gen[TestDag] =
+		def nonterminalGen(p: Gen.Parameters): Gen[TestDag] =
 		{
 			for(i <- 0 until nodeCount; nextDeps <- Gen.someOf(nodes).apply(p))
 				nodes += new TestDag(i, nextDeps)
@@ -27,7 +27,7 @@ object DagSpecification extends Properties("Dag")
 		}
 		Gen.parameterized(nonterminalGen)
 	}
-	
+
 	private def isSet[T](c: Seq[T]) = Set(c: _*).size == c.size
 	private def dependenciesPrecedeNodes(sort: List[TestDag]) =
 	{
diff --git a/util/process/src/test/scala/ProcessSpecification.scala b/util/process/src/test/scala/ProcessSpecification.scala
index f48a8282c..6298ce544 100644
--- a/util/process/src/test/scala/ProcessSpecification.scala
+++ b/util/process/src/test/scala/ProcessSpecification.scala
@@ -8,7 +8,12 @@ import Process._
 
 object ProcessSpecification extends Properties("Process I/O")
 {
-	implicit val exitCodeArb: Arbitrary[Array[Byte]] = Arbitrary(Gen.choose(0, 10) flatMap { size => Gen.resize(size, Arbitrary.arbArray[Byte].arbitrary) })
+	implicit val exitCodeArb: Arbitrary[Array[Byte]] = Arbitrary(
+		for(size <- Gen.choose(0, 10);
+			l <- Gen.listOfN[Byte](size, Arbitrary.arbByte.arbitrary))
+		yield
+			l.toArray
+	)
 
 	/*property("Correct exit code") = forAll( (exitCode: Byte) => checkExit(exitCode))
 	property("#&& correct") = forAll( (exitCodes: Array[Byte]) => checkBinary(exitCodes)(_ #&& _)(_ && _))
@@ -99,7 +104,7 @@ object ProcessSpecification extends Properties("Process I/O")
 			val process = f(a, b)
 			( process ! ) == 0 && sameFiles(a, b)
 		}
-	private def sameFiles(a: File, b: File) = 
+	private def sameFiles(a: File, b: File) =
 		IO.readBytes(a) sameElements IO.readBytes(b)
 
 	private def withTempFiles[T](f: (File, File) => T): T =
@@ -112,7 +117,7 @@ object ProcessSpecification extends Properties("Process I/O")
 			temporaryFile1.delete()
 			temporaryFile2.delete()
 		}
-	}	
+	}
 	private def unsigned(b: Int): Int = ((b: Int) +256) % 256
 	private def unsigned(b: Byte): Int = unsigned(b: Int)
 	private def process(command: String) =