链接VNCserver显示灰屏

大家好，今天在AIX7.1上安装了vncserver，启动后用vncviewer连接后一直显示是黑屏，请大家帮忙看看是什么原因。谢谢。
1.安装vncserver
rpm -ivh vnc-3.3.3r2-6.aix5.1.ppc.rpm
2.启动并设置密码
run:vncserver
3.用vncviewer链接vncserver显示黑屏。
配置如下：
bash-3.2# tail -f .vnc/xstartup
#!/bin/sh

xrdb $HOME/.Xresources
xsetroot -solid grey
xterm -geometry 80x24+10+10 -ls -title "$VNCDESKTOP Desktop" &
#twm &
/usr/dt/bin/dtsession &

bash-3.2# tail -f .vnc/netus241:1.log
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -240
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -239
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -232
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -26
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -65530
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -224
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -223
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -32768
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -32767
18/10/11 06:09:54 rfbProcessClientNormalMessage: ignoring unknown encoding type -32766
知道是什么问题的兄弟麻烦告知下，谢谢。

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