Jad, sis to jar

speedy,
u need to have some clarification about jad, jar and sis format first.
JAR is java application resource or java archive simply, u can see its contents by opening it in winrar or in winzip (for winzip change the extension to .zip from .jar. jad file is just a descriptor for the jar file. u can't install a java game without a jar file. u can see the contents of a jad file by opening it in notepad. jar file contains the actual application, not the jad file.
to install a java application u need to have at least jar file with u. if u have a jad file without a jar then u cannot install it. for over the air downloads, u may click on a jad link but actually the game is installed from a jar file in the same directory on the server. these applications are written in java.

sis stands for symbian installation system file. it contains the resources for the application in files like DLL, APP, RSC, R**, Aif etc. it utilises a totally different approach from java. these files are actually written in C++ and the compiled using a symbian SDK. after compilation these are packed in an installation package in sis format to be sent to phone.
so u see they have totally different approaches to get the job done.
i know sis applications are ported from symbian S60 platform to symbian UIQ platform and viceversa, but i have never heard of conversion from sis to java.