
Hi and welcome to CD :) Have answered this under your Guest post already!
> We think he may be doing it in protest!!<
It's easy to feel that way :P but fortunately dogs don't bear grudges etc :D It is more likely that he is anxious when you leave him during the day - more often than not, in those circumstances dogs eliminate almost immediately after being left but due to stress rather than "I'll make them suffer!" ;)
Before beginning to leave him for 4 hourly periods, did you try to get him used to short periods on his own? Also, when crated overnight, is he in the same room as you?
Teri