@kitty1990,
I've a similar but differently worded point of view as Chai -
Acceptable in your university or not, the reason many universities won't allow it - especially within a particular class but not limited to that - is because of the power differential. I think they are right. He can favor you re grades, or potentially cut your grades down for the wrong reasons. Even without the grade business, it's a matter of professional trust not to hit on those in your charge.
Your behavior, which I assume is because you think he is so wonderful (many get crushes on teachers), can also be taken as sucking up for special grading. At least get past any of your classes with him before you sting like a bee and get your wish.
Over the years, famous people have married their teachers. Many more crushes have turned things into a mess instead. Look around and find a fellow student to crush on.