title: Why does build break with Akka 2.4-SNAPSHOT missing?
body: <p>I have this in my <code>build.sbt</code>:</p>
  
  <pre><code>libraryDependencies += "com.typesafe.akka" %% "akka-actor" % "2.4-SNAPSHOT"
  
  libraryDependencies += "com.typesafe.akka" %% "akka-slf4j" % "2.4-SNAPSHOT"
  </code></pre>
  
  <p>When I compile it, it says:</p>
  
  <pre><code>::::::::::::::::::::::::::::::::::::::::::::::
  [warn]  ::          UNRESOLVED DEPENDENCIES         ::
  [warn]  ::::::::::::::::::::::::::::::::::::::::::::::
  [warn]  :: com.typesafe.akka#akka-actor_2.10;2.4-SNAPSHOT: not found
  [warn]  :: com.typesafe.akka#akka-slf4j_2.10;2.4-SNAPSHOT: not found
  [warn]  ::::::::::::::::::::::::::::::::::::::::::::::
  </code></pre>
  
  <p>Why is that? Even in here <a href="http://doc.akka.io/docs/akka/snapshot/intro/getting-started.html" rel="nofollow">http://doc.akka.io/docs/akka/snapshot/intro/getting-started.html</a> it says it must exist.</p>
  
  <p>In its directory</p>
  
  <blockquote>
    <p>sbt-version
        [info] 0.12.1</p>
  </blockquote>
  
  <p>In my home user's directory:</p>
  
  <pre><code>$ sbt sbt-version
  [info] Set current project to alex (in build file:/Users/alex/)
  [info] 0.13.7
  </code></pre>
  
  <p>Even after this <code>sbt.version=0.12.4</code>, the error remains.</p>
  
  <pre><code>// name := "my_name123"
  
  version := "0.1"
  
  //scalaVersion := "2.10.4"
  
  resolvers += "Akka Snapshot Repository" at "http://repo.akka.io/snapshots/"
  
  resolvers += "Typesafe Repository" at "http://repo.typesafe.com/typesafe/releases/"
  
  //resolvers += "typesafe-snapshots" at "http://repo.typesafe.com/typesafe/snapshots/"
  
  scalacOptions in ThisBuild ++= Seq("-unchecked", "-deprecation", "-optimise") // , "-feature"
  
  libraryDependencies += "com.typesafe.akka" %% "akka-actor" % "2.4-SNAPSHOT"
  
  libraryDependencies += "com.typesafe.akka" %% "akka-slf4j" % "2.4-SNAPSHOT"
  
  unmanagedResourceDirectories in Compile &lt;+= baseDirectory( _ / "src" / "main" / "scala" )
  
  unmanagedResourceDirectories in Compile &lt;+= baseDirectory( _ / "src" / "main" / "java" )
  
  libraryDependencies += "org.scalatest" %% "scalatest" % "2.2.0" % "test"
  </code></pre>