You can download the plugin at: http://sourceforge.net/projects/jext/files/OldFiles/antwork_plugin.zip/download
You have to enable the Jext Console to see the Apache Ant output (menu: Edit→Options…–General Panel), because Ant messages are redirected to the Jext console.
You can configure the Ant call in the Jext menu: Edit→Options…– Plugin Options–Antwork Plugin Panel; here you can set Ant home directory and the path to your build file.
You can start AntWork in the menu: Plugins→Ant→Work Now! In the appearing dialog box you can enter the target which you want to compile.
javac error occurs in the Ant run, an error list opens within Jext. With a
double click on the error message you jump to the error in the specified Java source file.