By default Package.path is set to just use what is in the website directory. This is consistent with the reactionary server. I think this is okay if the documentation tells people to use a directory structure like what the reactionary server expects. You can add to the path like this:
at the end of server.luan:
import "Package"
Package.path = Package.path .. ";java:jeans/?.luan"
to import:
import "lib/Jtp"
or more generally:
at the end of server.luan:
import "Package"
Package.path = Package.path .. ";?.luan"
to import:
import "java:jeans/lib/Jtp"