I am having the same trouble with my 8707. I tried downloading a .jar file from the internet to my handheld, no luck My phone put a '?' on the .jar file so it seems that it doesn't recognise .jar.
Originally Posted by JSanders
jar and jad file are for Over The Air downloads, via your browser, which you can't use until you get a Blackberry Data Plan
What is a Over The Air download? Is it about using a phone browser?