I have solved the problem by using porttunnel and ip-tools.
1.I watch which port logmein used.And this port is TCP 2002.
2.I add a new set for porttunnel.
In 2002/single/any
Out 8080/computer name/any(my proxy using port 8080 )
then I turn the logmein service off .
3.start the porttunnel ,then stop it.
4.start service in sequence:
logmein,porttunnel,logmein maintenace service.
It's all.
I have the same problem too.
I think the problem is that proxy server will check what version/type the browswer you use,like
IE5.0, IE6.0,Netscape,etc.
But our app did not send any information about browser version.