diff --git a/akka-core/src/main/scala/stm/Vector.scala b/akka-core/src/main/scala/stm/Vector.scala
index b76281b909..a526906115 100644
--- a/akka-core/src/main/scala/stm/Vector.scala
+++ b/akka-core/src/main/scala/stm/Vector.scala
@@ -326,7 +326,7 @@ object Vector {
   @inline
   private[stm] def array(elems: AnyRef*) = {
     val back = new Array[AnyRef](elems.length)
-    Array.copy(elems, 0, back, 0, back.length)
+    Array.copy(elems.toArray, 0, back, 0, back.length)
 
     back
   }