It doesn't matter if you run your JUnit tests from a command line, from an IDE, or from "ant", you must define your CLASSPATH settings correctly. Here is what recommended by the JUnit FAQ with some minor changes:

To run your JUnit tests, you'll need the following elemements in your CLASSPATH:

* The JUnit JAR file.

* Location of your JUnit test classes.

* Location of classes to be tested.

* JAR files of class libraries that are required by classes to be tested.

If attempting to run your tests results in a NoClassDefFoundError, then something is missing from your CLASSPATH.

If you are running your JUnit tests from a command line on a Windows system:

set CLASSPATH=c:Ajunit-4.4.jar;c:Btest_classes;

c:Btarget_classes;c:D3rd_party.jar

If you are running your JUnit tests from a command line on a Unix (bash) system:

export CLASSPATH=/A/junit-4.4.jar:/B/test_classes:

/C/target_classes:/D/3rd_party.jar