Multiple applications

[eluser]Capt. Kirk[/eluser]
Hello there!

How can I keep multiple applications using CI? I mean, the manual says that I must have the same structure of folders as controler, view, etc, but do I have to copy all the folders as library, helper, errors and model too? I mean, how can I use my all UDF and classes in all projects? How can I also call each application without setting the $application_folder variable at index.php, since it allow one application at the time?

Thanks for any help you can give.

Best regards.