I have the exact same problem and we also use ISA proxy.
Did you find a solution for this?
Version 3.2 works fine.
Any answers to this. I am using a Virtual Windows session trying to connect, but get the error mentioned. Version 3.2.10.09 works fine. 188.8.131.52.80 doesn't. Same exact properties for both versions.
I still have not come across a solution. Please post here if you happen to come across one...
I think I have found a solution.
Run the command prompt (CMD) in windows and type in the following:
setx _JAVA_OPTIONS -Djava.net.preferIPv4Stack=true
I got this from a java developer and now I'm able to connect