Hi Stormi,

I'm wondering if his not using the toilet might be just plain disobedience? You say you've tried a star chart and it hasn't worked, what other options have you discussed with your husband for encouragement/discouragement?
Your DS's comment about the toilet being 'boring' makes me wonder if he isn't just plain ignoring you, rather than it having some physical reason - although I would also be taking him to the doctor to get a check-up to rule this out.

I'm assuming that the general rules you and your DH use to deal with bad behaviour haven't worked in this instance, so you need to find something that really makes a difference to him, whether it be positive or negative.
With the weeing, I know some boys who are more encouraged to use the toilet if it has a ping-pong ball with a target on it floating in the bowl to aim at.

With regard to discouragement, (and here I'm risking being blasted for not suggesting a 'gentle parenting' approach) I know of someone at the end of their tether cleaning their son up with the outside hose (not hard, just thorough) so that the clean-up isn't a 'reward' warm fuzzy time with Mum where you get to feel nice and clean and scented with wipes, but a brisk rub-down outside with cold water.
As it's summertime now, this is quite do-able without causing physical trauma. This worked for some friends of mine, it only happened twice and he decided that using the toilet was preferable. I'm not suggesting that this is the only solution, or even one you want to use, but it is one that I know has worked for someone.

Personally I believe, IF this is a behavioural rather than a physical issue, that there needs to be some sort of consistent consequence for him messing his pants. Encouraging him and telling him that it is not socially acceptable hasn't worked for you, so there needs to be some form of discouragement that will make him decide to change his mind about doing it - basically, the discouragement needs to cost him more effort than going to the toilet, so he decides it isn't worth it.

Kerrie