I just now build 2.4 from scratch and it built fine.
Do this. Look at the META-INF/Manifest.mf file in thirdparty/javassist/lib/javassist.jar and verify that it is the 3.2 version.
Then look for where you have the 3.3 version of javassist installed. For example, as part of a classpath (not likely, the build sets its own classpath), or in your Java endorsed directory (highly likely). If the file is in your endorsed directory, remove it.
Thank you Peter :)
I have one more time builded the portal. This time all without error. I do not know why from the beginning so it has turned out.
The build has any stochastic character. I in general changed nothing, have simply entered command one more time.
In any case works.