potential hack

i was on chat there from 10am - 10.50 and noticed a few people mention trades not working ie their naterials getting taken but not recieving any materials in trade or offers, then a player stated they had just recieved 20 odd new friends and asked what happened, we told him he had been accepted to a guild and he then asked for the guild master of rbc (myself) to speak to him as that was the guild he was in but did not have RBC before his name in chat.
We both logged in and out and once back, i offered an invite to the guild and he accepted and his guild tags appeared ...
Reported to MOD_Bones at 10.46 who directed me to here to report the issue.