As per this conversation: http://apache-wicket.1842946.n4.nabble.com/how-to-get-https-port-number-in-Wicket-1-5-td4295139.html
it seems that POST params are not properly processed and made available as PageParameters. Can anyone say whether this is intended behavior or not? I will attach a Quickstart to demonstrate.
Martin's proposed fix is straightforward, but I am not comfortable enough with Wicket internals to say whether or not this would break something.