Multiple implicits with the same name cause a compilation error

multiple_implicits.scala

package bmrk.eod.parsing.examples.inference
import java.util.SortedMap

object Implicits {
  implicit def implicitDef[T <: AnyRef](key:String,columns:SortedMap[String,String]) (implicit m:Manifest[T]):T = {
    null.asInstanceOf[T]
  }

  // If the next method is removed this file will compile
  implicit def implicitDef[T <: AnyRef](key:String,columns:List[(String,String)]) (implicit m:Manifest[T]): T = {
    null.asInstanceOf[T]
  }
}

class Test {
  import Implicits._

  def someMethod[S](implicit anotherMethod:(String,SortedMap[String,String]) => (Manifest[S]) => S) = {
    anotherMethod(null, null)
  }

  val foo = someMethod[String]
}