Changed Sonar web.context, now ant task fails - ant

Question

I had a working sonar/jenkins installation, where sonar was installed on localhost:9000 and jenkins was on localhost:8080. I then wanted to hide those services behind Apache and protect them behind Crowd-authenticated account access.
So first, I relocated Jenkins to localhost:8080/jenkins and proxied it. Which worked.
Then I relocated Sonar to localhost:9000/sonar and proxied it. Which also worked.
But now, when I try to execute the Sonar task from within the build script in Jenkins, I get the following error:
sonar:
[sonar:sonar] Apache Ant version 1.7.1 compiled on April 26 2010
[sonar:sonar] Sonar Ant Task version: 1.2
[sonar:sonar] Loaded from: file:/usr/share/ant/lib/sonar-ant-task-1.2.jar
[sonar:sonar] Sonar work directory: /var/lib/jenkins/jobs/buzzcartes/workspace/.sonar
[sonar:sonar] Sonar server: http://localhost:9000
BUILD FAILED
org.sonar.batch.bootstrapper.BootstrapException: http://localhost:9000/api/server /version
at org.sonar.batch.bootstrapper.Bootstrapper.getServerVersion(Bootstrapper.java:71)
at org.sonar.ant.SonarTask.checkSonarVersion(SonarTask.java:225)
at org.sonar.ant.SonarTask.execute(SonarTask.java:188)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:288)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.Target.execute(Target.java:357)
at org.apache.tools.ant.Target.performTasks(Target.java:385)
at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1337)
at org.apache.tools.ant.Project.executeTarget(Project.java:1306)
at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
at org.apache.tools.ant.Project.executeTargets(Project.java:1189)
at org.apache.tools.ant.Main.runBuild(Main.java:758)
at org.apache.tools.ant.Main.startAnt(Main.java:217)
at org.apache.tools.ant.launch.Launcher.run(Launcher.java:257)
at org.apache.tools.ant.launch.Launcher.main(Launcher.java:104)
Caused by: java.io.FileNotFoundException: http://localhost:9000/api/server/version
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1610)
at java.net.URLConnection.getContent(URLConnection.java:748)
at org.sonar.batch.bootstrapper.Bootstrapper.remoteContent(Bootstrapper.java:123)
at org.sonar.batch.bootstrapper.Bootstrapper.getServerVersion(Bootstrapper.java:69)
... 18 more
I've updated the configuration in Jenkins to reflect the new location of http://localhost/sonar so I'm not sure where the http://localhost:9000/ is now coming from. I've looked in a variety of config files so far with no joy and Google isn't turning up any good answers so far. Any pointers would be most welcome.
Oh, my sonar task in build.xml looks like this:
<target name="sonar" depends="compile">
<!-- list of mandatory Sonar properties -->
<property name="sonar.sources" value="${basedir}/src" />
<!-- list of optional Sonar properties -->
<property name="sonar.projectName" value="buzzcartes" />
<property name="sonar.binaries" value="${basedir}/build" />
<property name="sonar.tests" value="${basedir}/test" />
<property name="sonar.libraries" value="${basedir}/lib" />
<sonar:sonar key="com.benjasoft:buzzcartes" version="0.1-SNAPSHOT" xmlns:sonar="antlib:org.sonar.ant" />
Thanks!

Answer 1

Try so set the sonar.host.url parameter
Maven
<sonar.host.url>http://wherever.sonar.com:9000</sonar.host.url>
Ant
<property name="sonar.host.url" value="http://wherever.sonar.com:9000" />
Strangely it is not documented here, but mentioned in the ant task guide.