Just to clarify, this was not my bug, it seems like some sort of memory corruption in the client, which puts wrong number into address.
I have no problem with large trades so long as they are small for you personally and you are not afraid to lose them.
Also, withdraw by smaller chunks to lessen the probability of another such error.
I will save a screenshot before clicking "send" on each withdrawal from now on to make absolutely sure it wasn't my mistake.
Somebody just deposited 60 000 NXT, so we'll see