hacker or not?

i wanted to ask to someone with more knowledge than me if this is something possible or not.
I've been attacked by a sin,alone and only with it's own buffs.
I know sins attack fast,i just wanted to know if they can really attack THAT fast.
Here is a part of my combat log.

2011.02.04 12:22:15 : You received 371 damage from xxxxx.
2011.02.04 12:22:15 : You received 37 damage from xxxxx.
2011.02.04 12:22:15 : You received 368 damage from xxxxx.
2011.02.04 12:22:15 : You received 37 damage from xxxxx.
2011.02.04 12:22:15 : xxxxx has inflicted 540 damage on you by using Swift Edge V.

i got more logs against that same char,all with similar things.
Is it possible?
i edited his name cause if a pro player tells me it's probably an hack,i'll pm the char name directly to a gm

 

lol ofc it possible.

 

its possible if it is just a normal attack..
:wink:

 

I've gotten off 7 thingies in one second once, autoattack autoattack autoattack