The distributed jetty-hsqldb zip with a preinstalled flavor (distribution-flavor-jetty-hsqldb) provides a main WikiDescriptor with the information about host and port. Those information points XWiki by default to localhost without any port set.
So the default is already wrong, since jetty is starting on 8080. At least this port should be recorder. But it would be even better to not provide any WikiDescriptor if that's possible so it's computed at first start.