InfoPath 'Submit' - Where Art Thou?

An initial couple of sessions with the InfoPanel Beta certainly highlights for me what a great product MS have produced.  For me - it is so much more intuitive and user friendly than Altova's Authentic, although the fact that Authentic is now free means that another look is warranted.

Suprisingly, given the recent quality of MS's betas, I seem to get at least one exception each time I use InfoPath.  They largely seem to occur when I reposition existing controls on a form.

While I can convert an exisiting XML schema into a rich form in about 20 seconds, save form data to XML and export the form to a binary representation (and an XSL transform to DHTML), I can't work out how to 'submit' a form to a web service or file.  The 'submit' button on the File menu remains stubbornly disabled no matter what I try.

I suspect it might be because I have only installed the InfoPath 2003 Beta and not Office 2003 Beta.  A search of the documentation hasn't helped.  Ideas?