import sbt._
import Keys._
object MyBuild extends Build {
  // ...
  val getJars = TaskKey[Unit]("get-jars")
  val getJarsTask = getJars <<= (target, fullClasspath in Runtime) map { (target, cp) =>
    println("Target path is: " + target)
    println("Full classpath is: " + cp.map(_.data).mkString(":"))
  }
  lazy val project = Project(
    "project",
    file("."),
    settings = Defaults.defaultSettings ++ Seq(getJarsTask))
}

Add task 'get-jars' prints classpath
Add task 'get-jars' prints classpath
