Just report and move on to the next hand...

You cant tell by looking at the history if it was done deliberatly or not.

I've had a sucky dialup connection and folded AA to a preflop push (over my raise) ... Then I came back the guy ranted at me for "disconnecting" on his push with QQ (he setted) till I pointed out that I had AA(he didnt bother checking the history).

Disconnects happen at bad times, nothing to do about it other than report and move on... if he has a history of it, they will see it, if not, then it was bad luck.

ps: Looking back on that hand I still grin... I logged on to:

Jerk: ****** ****** ****** I reported you for ****** disconnecting ******* ****** *********** you ******** they will lock your ****** account ***** *******
Laeelin: .... yeah, I didnt want to call your preflop push and folded my rockets. Check the hand history.
Laeelin: Because you like reporting so much, I returned the favor.
Jerk: ********* ******** ******** ********** ***** *****
Jerk has left the table.