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7. I meet man in IRC who offer me to make deal, he send me ~9000$ BTC I send him ~3000$ liberty reserve (simple trade) minus some fees, I accepted, trade was made. btc rate in that day was ~0.30/BTC.
8. After month after trade was made (with man from IRC) I noticed that my mtgox.com acount is blocked.
9. Mtgox.com starting asking from where I get those 9000$ BTC, I explained.
After the deal with the stranger, have you done any BTC deposits to your mtgox account?
No.
How exactly did mtgox refer to the 9000$ BTC in question, in their inquiry?
He blocked my mtgox.com account, and started asking from where i received 9000$ , I explained him.
Did you specifically generate a new address for that transaction (deal with the stranger), and have you ever used that same address to receive bitcoins before or afterwards?
I was "playing" with bitcoin client , I created some addreses (curently I don't realy understand why there is function to create new addreses ). I was using one bitcoin address with mtgox.com and second for trade (with that man from IRC), to trace money income into my bitcoin client. I never used those addreses for any other activiti. I also have some more addreses in my bitcoin client, but they not in use.
I never used bitcoin client before I was registered on mtgox.com, it was my first time.