Its about the first time in a couple of months I have done any work with Grails, and I had forgotten how pleasant it is to work with!
However, over the weekend I ran into a couple of interesting issues, one of which I would like to share here, in the hope it may save someone else the time to track it down:
In Grails release 1.0.3 the rules of precedence for form posts have changed, if you suddenly see strange 404 page not found errors after upgrading, then look at your usage of submit buttons on the page as described below: