Had an interesting (in an annoying sort of way) experience with ATC yesterday coming back from Florida in the Citation. We were departing Ocean Reef (07FA) after pax pickup. Ocean Reef is a private airport on an island south of Miami. VFR only and no charts, so on the way in we asked the final controller (Miami Approach) what the best way was to pick up our IFR outbound. He told us to just contact them on that freq and pick it up in the air after departure. So….that is just what we did. After climbing above 1000' I call up Miami and ask to pick up our clearance. Same freq, but different controller. He responds rather curtly with a 'you are not in my airspace, you need to contact Homestead Approach'. Ok, fine. We shift to Homestead's freq and call them. At this point, we are around 4500' and Homestead tells me I'm above his airspace and I need to descend to 4000 so he can work me. We do that and he gives us our clearance, then vectors us north and hands us back to Miami. As soon as I check in with Miami (and give him the assigned heading), he comes back all put-out and ****ed off and gives me an immediate 70 degree turn to the west. Thankfully, we were not with Mr Grumpypants very long. WTF? Was this guy just being an jerk, or did we just fly into the middle of some hate between Homestead and Miami?