Jaring with external packages

[Murat Balkan]

Hi all,
I packed my classes in a jar file and when I try to run this jar I get classnotfound exceptions about external apis such as javamail,jdbc apis so on. The problem is that I have lots of these in my project.
My question is
is there a way that my own classes in my jar file see these external apis.
(they are all in classpath and when executing from standart class files they all work fine)
I do not want to add these external packages to the jar cause they are installed on the client machine and their classpath entries are correctly set.
Thank you,
Murat