[Koha] Date problems adding new members

On a new Koha 2.2.8 using either the default or npl templates and adding a new member leaving the joining and expiry date fields blank results in no date being inserted. Also when manually entering the joining date the expiry date is still not auto calculated. I checked liblime's demo and it works there. Can someone point me to the section of code that's supposed to do this? I've looked at memberentry.tmpl for both templates and memberentry.pl and am having difficulty following what the code is doing. There's also nothing in the error log. Thanks, Mike D.