Rahul,
Instead of putting your jar file in /packages/Proj_UploadFile_Service/code/jars, place it into /packages/Proj_UploadFile_Service/code/jars/static/ - that will work.
I have worked with a team in the past where there were shared IS instances, i.e. single IS instance hosting application packages for different teams. The WIO team had a rule - applications host their own jars. They would not allow any application jar into the lib/jar for the reason that it was easy to track application-jar tie up besides, if application ever needs to be moved or removed - the jars moved along with application.
My 2 cents.
~Rohit