diff --git a/util/collection/Util.scala b/util/collection/Util.scala
index cceb1ec99..0b6b25118 100644
--- a/util/collection/Util.scala
+++ b/util/collection/Util.scala
@@ -6,7 +6,10 @@ package sbt
 object Util
 {
 	def separate[T,A,B](ps: Seq[T])(f: T => Either[A,B]): (Seq[A], Seq[B]) =
-		((Nil: Seq[A], Nil: Seq[B]) /: ps)( (xs, y) => prependEither(xs, f(y)) )
+	{
+		val (a,b) = ((Nil: Seq[A], Nil: Seq[B]) /: ps)( (xs, y) => prependEither(xs, f(y)) )
+		(a.reverse, b.reverse)
+	}
 
 	def prependEither[A,B](acc: (Seq[A], Seq[B]), next: Either[A,B]): (Seq[A], Seq[B]) =
 		next match