When should I use Scala's `package` special identifier?

In Scala, you can define package objects. It seems thus that you can access that package object by writing the package name, and then `package`:

// file package.scala in src/com

package com
package object test {
  val Version = 2
}

// file Test.scala in src/test

package test
object Test {
  def main(args: Array[String]) {
    val p = com.test.`package`          // get ref on package object
    val v1 = com.test.`package`.Version // (1) get val
    val v2 = com.test.Version           // (2) get val
  }
}

What is the difference between (1) and (2)? In some cases, I've had to write the extra `package` for my code to run. Should there be a difference or is it a compiler bug?

Moreover, what does e.g. this line mean, in Predef.scala?

scala.`package`   // to force scala package object to be seen.