answer for stackoverflow http://stackoverflow.com/questions/13921168/how-to-get-application-path-in-dependency-resolvers/13922654#13922654

Build.scala

import sbt._
import Keys._
import PlayProject._

object ApplicationBuild extends Build {

    val appName         = "so13921168"
    val appVersion      = "1.0-SNAPSHOT"

    val appDependencies = Seq(
      "info.schleichardt" %% "play-2-mailplugin" % "0.6.1"
    )

    val main = PlayProject(appName, appVersion, appDependencies, mainLang = SCALA).settings(
/*
Stackoverflow question was:
How to get application path in dependency resolvers?
 have local maven repository in repo subdirectory. Need to point to that directory in resolver path, but examples below doesn't work. How to get application path in this config ?
*/
      resolvers <+= baseDirectory { base => 
        "local maven repo" at ("file://" + base.getAbsolutePath + "/repo")
      }
    )
}