Packaging a BlackBerry application project for multiple versions of BlackBerry Device Software
You can create a BlackBerry® device application that is compatible with multiple versions of the BlackBerry® Device Software. When you package your BlackBerry application project (and it's dependent projects) for multiple versions of the BlackBerry Device Software, the BlackBerry® Java® Plug-in for Eclipse® creates the application files for distribution to BlackBerry device users that run the versions of the BlackBerry Device Software that you include in your BlackBerry application project.
When you distribute your BlackBerry device application by using the BlackBerry® Desktop Software or the BlackBerry® Enterprise Server push service, the BlackBerry Java Plug-in for Eclipse creates one master .alx file in the Standard folder of your BlackBerry application project.
When you distribute your BlackBerry device application over the Internet, the BlackBerry Java Plug-in for Eclipse creates the .jad and .cod files for each version of the BlackBerry Device Software in the Web folder of your BlackBerry application project.
You can use the auto-signature feature in the BlackBerry® Java® Plug-in for Eclipse® to sign the .cod files automatically after you package a BlackBerry application project.