It's a bit narcissistic to make a post saying that it is my B-day, so I feel making a post in which you are able to post "HEY I'M ANOTHER YEAR CLOSER TO MY DEMISE, PAY ATTENTION TO ME!" would be a bit nicer and more interesting, then just simple posting. Me, me, me, my b-day not yours piss off.
So when it is your birthday please, by all means be the self centered person you've always been deep down inside and post to your hearts content.
P.S. also you may post to either say Happy B-Day or tell those you've always wanted to, TO SHUT THE HELL UP WE NO LONGER CARE ABOUT YOU...also happy b-day.