Finally even me landed in the JUnit 4 planet.
The main difficulty in migration from 3.8.* is the class AllTests : a class with all the tests in it from where you can run all application tests in one shot.
The 4.x way is to use JDK (>=5) annotation, but if you for some reason have to use the JDK 1.4 you have two solutions. The one I prefer is to use junit 3.8.x but if you cannot tolerate the missing of JUnit 4.x in the attached PDF you’ll find the standard 4.x way (with annotation) and a workaround for using the old JUnit TestSuite syntax.