When I try and debug an ant project, I get the following:

/home/quintin/.netbeans/dev/var/cache/executor-snippets/debug.xml:72: 
java.lang.NullPointerException
        at org.netbeans.modules.debugger.jpda.ant.JPDAStart.execute(JPDAStart.java:222)
        at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:288)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        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.module.bridge.impl.BridgeImpl.run(BridgeImpl.java:278)
        at org.apache.tools.ant.module.run.TargetExecutor.run(TargetExecutor.java:498)
        at org.netbeans.core.execution.RunClassThread.run(RunClassThread.java:151)
BUILD FAILED (total time: 0 seconds)


All my installations do this. I tried removing the cached debug.xml ant script, tried a new userdir. Nothing helps. 

Workaround:
1. Open project properties
2. Under the run page enter the following options for "VM Options":
  -Xdebug -Xrunjdwp:transport=dt_socket,address=8000,server=y,suspend=y
3. Confirm the properties window (press OK)
4. Run your project. It will now wait for a debugger connection
5. On the Debug menu, select Attach Debugger
6. Select the following values for each field:
  Debugger: Java Debugger (JPDA)
  Connector: SocketAttach
  Host: localhost
  Port: 8000
  Timeout: 2000
7. Click OK. 

The debugger should now attach to the process, and the process will start running.