"Unable to contact a Locator service" in Tutorial

I am evaluating GemFire and have performed the installation on three nodes.  So far everything has gone smoothly.  When trying to run the tutorial/samples, (Running the Tutorial) I am told to edit the GemfireDAO.java file and change the line in here to point to the server running my locator service (which is running):

Cache cache = new CacheFactory()

  .set("locators", "localhost[55221]")

  .set("mcast-port", "0")

  .set("log-level", "error")

  .create();

I changed "localhost" to my server running my locator (which I verified was pingable from the server where I was changing the GemfireDAO.java file) to read:

Cache cache = new CacheFactory()

  .set("locators", "mrwhite[55221]")

  .set("mcast-port", "0")

  .set("log-level", "error")

  .create();

Then, when I run the command:

   java com.gemstone.gemfire.tutorial.Peer

I get the following:

Exception in thread "main" com.gemstone.gemfire.GemFireConfigException: Unable to contact a Locator service.  Operation either timed out or Locator does not exist.  Configured list of locators is "[localhost(null)<v0>:55221]".

        at com.gemstone.org.jgroups.protocols.TCPGOSSIP.sendGetMembersRequest(TCPGOSSIP.java:192)

        at com.gemstone.org.jgroups.protocols.PingSender.run(PingSender.java:86)

        at java.lang.Thread.run(Thread.java:724)

I'm jus twondering why it is trying to contact "localhost".  Is there some other file that needs to be modified that was not in the instructions?