problem with jar

hey guys.. i am currently doing a project and i have finished it.... i developed it using eclipse.... the project work just fine when i runs it from eclipse...the class project.class contains the main function ..but when i created a jar and tried executing it i gets an error saying could not find main class....i have set the manifest file right...so now i dont know whats the problem...

[395 byte] By [dare-devila] at [2007-11-27 1:38:58]