First I changed into something green.
Then I posted this until he quoted me back:
[quote="[NPC] Odanodan"]Mr. Odanodan, lots of fortune
Gold and Green, filled with luck
One-leaf two-leaf three-leaf four-leaf clovers!
Let's see if there's a trigger word![/quote]
I quoted him back with random comments
We went back and forth for several (6+?) posts
I changed back to my non-green avatar and posted the above code once more
The Golden Clover appeared in my inventory
There's no alert saying you've received it, nor is there a notice that he quoted you.
You just have to pay attention.
Anyway, just wanted to mention how I did it.
There are lots of people saying you have to tip his posts to get the item grant.
I never once tipped a post, and I still got it.
I'm assuming there's some random element to it? I'm not sure.
But good luck!