The jar file coldn't be launched.

Hi, thanks for the welcome and to read me.
Yes, I tried whith older java, but it did the same chose.
the backpropagation class, was useful for me, but now the problem is that I will use others applications of java, and I have still the problem.
for example, I tried to used a Java Neural network simulator, and ask me that "To be able to use JavaNNS, you have to have Java Runtime Environment (or JDK, which contains it) installed. JavaNNS has been tested to work with Java 1.3, Java 1.2.2 might also work, though problems with file management have been reported in certain environments"
when I did all the choses that to ask me, but nothing happend, and the console said "java.lang.Exception: The system couldn´t find the library SNNS_jkr"
JavaNNS couldn´t start.
at javanns.Network.<init>(javanns/Network.java:48)
at javanns.Snns.<init>(javanns/Snns.java:151)
at javanns.Snns.appletMain(javanns/Snns.java:278)
at javanns.Snns.main(javanns/Snns.java:258)

I guess that is a problem whit the libreries o my Java has to fail, but I am not sure.

any suggestion? please...

thanks

Are for my personal use, I have to use Artificial Neural Networks for a project, I got a few softwares frees, but almost all were wrote whit Java, and for that I need to use jar files. why?