I dunno man, I was up around 4000 cals per day, and I was gaining fat faster than I was muscle. I've since scaled it back down with some assistance from my trainer to try and keep my body fat from going out of control.
I'm at 6', 180, and still trying to gain, but I'm not going to be pushing that many cals any time soon.
I've been told by a few people to tweak your diet a little at a time. If you stop seeing gains, add 500 cals, if you start gaining too much fat, subtract 500 cals. Very broad, and I took out carbs rather than pure cals, but you get the idea.
Curious to know if anyone else has tried this tho...