[Tinyos-help] Mviz running promblem

[4song]

HI, I have a problem about running Mviz on the tinyOS-2.x in Cygwin

this is the running result below
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ysl4Song at oem-ff4d4c4bb50  /opt/tinyos-2.x/apps/MViz
$ tos-mviz -comm serial at COM4 MVizMsg

d:\cygwin\opt\tinyos-2.x\support\sdk\java\tinyos.jar;.
Making MVizMsg
Loading version
Loading interval
Loading origin
Loading count
Loading reading
Loading etx
Loading link <route>
./mote.gif
Exception in thread "main" java.lang.NullPointerException
       at java.util.Hashtable.get(Unknown Source)
       at net.tinyos.packet.Platform.get(Platform.java:23)
       at net.tinyos.packet.BuildSource.decodeBaudrate(BuildSource.java:201)
       at net.tinyos.packet.BuildSource.makeArgsSerial(BuildSource.java:227)
       at net.tinyos.packet.BuildSource.makePacketSource(BuildSource.java:138)
       at net.tinyos.packet.BuildSource.makePhoenix(BuildSource.java:87)
       at net.tinyos.mviz.MessageInput.createSource(MessageInput.java:72)
       at net.tinyos.mviz.MessageInput.<init>(MessageInput.java:51)
       at net.tinyos.mviz.DDocument.main(DDocument.java:303)
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the problem was when GUI getting start, the right side panel displayed nothing

ps. I have installed the Mviz program in one telosb mote

 thank you in advance,

 Walton