java.net.UnknownHostException: www.terracotta.org

java.net.UnknownHostException: www.terracotta.org

Getting the following error when Jboss server start up.
java.net.UnknownHostException: www.terracotta.org
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:177)
~[na:1.6.0_11]
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
~[na:1.6.0_11]
at java.net.Socket.connect(Socket.java:519) ~[na:1.6.0_11]
at sun.net.NetworkClient.doConnect(NetworkClient.java:158) ~[na:1.6.0_11]
at sun.net.www.http.HttpClient.openServer(HttpClient.java:394)
~[na:1.6.0_11]
at sun.net.www.http.HttpClient.openServer(HttpClient.java:529)
~[na:1.6.0_11]
at sun.net.www.http.HttpClient.<init>(HttpClient.java:233) ~[na:1.6.0_11]
at sun.net.www.http.HttpClient.New(HttpClient.java:306) ~[na:1.6.0_11]
at sun.net.www.http.HttpClient.New(HttpClient.java:323) ~[na:1.6.0_11]
at
sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:837)
~[na:1.6.0_11]
at
sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:778)
~[na:1.6.0_11]
at
sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:703)
~[na:1.6.0_11]
at
sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1026)
~[na:1.6.0_11]
at
net.sf.ehcache.util.UpdateChecker.getUpdateProperties(UpdateChecker.java:108)
[ehcache-core-2.6.5.jar:na]
at net.sf.ehcache.util.UpdateChecker.doCheck(UpdateChecker.java:72)
[ehcache-core-2.6.5.jar:na]
at
net.sf.ehcache.util.UpdateChecker.checkForUpdate(UpdateChecker.java:60)
[ehcache-core-2.6.5.jar:na]
at net.sf.ehcache.util.UpdateChecker.run(UpdateChecker.java:51)
[ehcache-core-2.6.5.jar:na]
at java.util.TimerThread.mainLoop(Timer.java:512) [na:1.6.0_11]
at java.util.TimerThread.run(Timer.java:462) [na:1.6.0_11]
Any solution for the root cause would be helpful.