When putting a .jad and .jar file on a website, make sure the MIMEtypes are configured properly!
I found information on how to do this:
http://www.onjava.com/pub/a/onjava/e..._3/index5.html
The web server MIMEtype needs to be configured:
.jad files
text/vnd.sun.j2me.app-descriptor
.jar files
application/java-archive
Also, most of the time, there's a limit on the size of the .jad file that can be downloaded Over-The-Air. I've been able to install a 100Kbyte application, but there can be problems installing a 200Kbyte application Over-The-Air, especially if the web server has size limits. For example, I've seen T-Mobile barf when trying to install anything over 70 kilobytes sometimes (at least during last fall).