You can add Ant debug configuration from the Edit configurations dialog (screenshot 4). Then you select Ant file, Java SDK for debugging session (screenshot 5).
Note. Plugin requires Java SDK to launch Ant: plugin uses build file module, project or any SDK for JDK list (the plugin searches for Java SDK in this order and uses first found).
Installation: use Idea plugins manager:
Supported Idea versions: Idea 8.1.x, Idea 9 (community and ultimate editions).
Please write to antdebugger at handyedit.com if there are errors / problems when using Ant debugger