Smack wont work behind proxy server

I am using the latest Smack 2.2.1

I have set the proxyPort, proxySet and proxyHost System properties and also tried to retrieve a URL successfully through a URLConnection.

However, when I try to connect to google talk I get:

Exception in thread “main” XMPPError connecting to talk.google.com:5222.: (502)

– caused by: java.net.ConnectException: Connection timed out: connect

at org.jivesoftware.smack.XMPPConnection.connectUsingConfiguration(XMPPConnection. java:281)

at org.jivesoftware.smack.XMPPConnection.(GoogleTalkConnection.java:36)

Any ideas what’'s wrong?

The normal google talk client works through my proxy.