or maybe more: "j'ai souhaité avoir dit au professeur" (or "j'aurais aimé dire au professeur"), if you meant you wish you could have said sthg to the professor but it's too late now.
But you can't leave the sentence like that, you need to precise what you wanted to say to the professor. Or you should use "parler" (=to speak) instead of "dire" (=to say).
yes, i think i was a little too vague. The sentence was: In my heart, I wish that I had told my teacher something.
aurayfrance, in using that rule u said, then if i constructed this sentence, would it be right?: A mon coeur, j’ai souhaité qu’on aie dit "the teacher about it" (<--- dunno how to translate that exactly). *sighs* sujonctif is soooo hard to understand.