D:\jbpm-installer>ant install.demo
Buildfile: D:\jbpm-installer\build.xml
download.jboss.check:
[echo] Checking JBoss AS download ...
download.jboss:
[echo] Getting JBoss AS ...
[get] Getting: http://downloads.sourceforge.net/jboss/jboss-5.1.0.GA.zip
[get] To: D:\jbpm-installer\lib\jboss-5.1.0.GA.zip
[get] Error getting http://downloads.sourceforge.net/jboss/jboss-5.1.0.GA.
zip to D:\jbpm-installer\lib\jboss-5.1.0.GA.zip
BUILD FAILED
D:\jbpm-installer\build.xml:72: java.net.UnknownHostException: downloads.sourcef
orge.net
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:195)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:529)
at java.net.Socket.connect(Socket.java:478)
at sun.net.NetworkClient.doConnect(NetworkClient.java:163)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:394)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:529)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:233)
at sun.net.www.http.HttpClient.New(HttpClient.java:306)
at sun.net.www.http.HttpClient.New(HttpClient.java:323)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLC
onnection.java:970)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConne
ction.java:911)
at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection
.java:836)
at org.apache.tools.ant.taskdefs.Get$GetThread.openConnection(Get.java:6
60)
at org.apache.tools.ant.taskdefs.Get$GetThread.get(Get.java:579)
at org.apache.tools.ant.taskdefs.Get$GetThread.run(Get.java:569)
Total time: 25 seconds
D:\jbpm-installer>
I think it's better if you down load those components before you install the jBPM. And, put it into the right directory which you could find in the build file.