I used the following launch command for the server:

@echo off
java -Xmx1024M -Xms1024M -jar minecraft_server.13w21b.jar nogui

After it loaded, I typed the "stop" command, which shuts down the server, but leaves a sloppy error, which I included below, as both text and image.

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2013-05-27 19:04:42 [INFO] Starting minecraft server version 13w21b
2013-05-27 19:04:42 [INFO] Loading properties
2013-05-27 19:04:42 [INFO] Default game type: SURVIVAL
2013-05-27 19:04:42 [INFO] Generating keypair
2013-05-27 19:04:42 [INFO] Starting Minecraft server on *:25565
2013-05-27 19:04:42 [INFO] Preparing level "world"
2013-05-27 19:04:42 [INFO] Preparing start region for level 0
2013-05-27 19:04:43 [INFO] Done (0.753s)! For help, type "help" or "?"
stop
2013-05-27 19:04:44 [INFO] Stopping the server
2013-05-27 19:04:44 [INFO] Stopping server
2013-05-27 19:04:44 [INFO] Saving players
java.net.SocketException: socket closed
at java.net.DualStackPlainSocketImpl.accept0(Native Method)
at java.net.DualStackPlainSocketImpl.socketAccept(Unknown Source)
at java.net.AbstractPlainSocketImpl.accept(Unknown Source)
at java.net.PlainSocketImpl.accept(Unknown Source)
at java.net.ServerSocket.implAccept(Unknown Source)
at java.net.ServerSocket.accept(Unknown Source)
at ik.run(SourceFile:61)
2013-05-27 19:04:44 [INFO] Saving worlds
2013-05-27 19:04:44 [INFO] Saving chunks for level 'world'/Overworld
2013-05-27 19:04:44 [INFO] Closing listening thread
2013-05-27 19:04:44 [INFO] Saving chunks for level 'world'/Nether
2013-05-27 19:04:44 [INFO] Saving chunks for level 'world'/The End
2013-05-27 19:04:45 [INFO] Stopping server

This is a screenshot of the error.
http://i.imgur.com/xrZ9etr.png

It has no other issues beside it looking strange when closing the server.