Please check this transaction in my account history: 2013/05/18 09:55:57 Withdraw 0.81385120 Bitcoin withdraw to 147gae1XZnB3F18HRusqKu3MfaH8Er2hpt
according to this: https://blockchain.info/nl/tx/0dd62e4644f1b7f47590edbeb860a7da794b0d51217bd0433ae4eaff7f54587d
the send address was 1PZmRkTrBv8sSn1mgYtjeVwJLtxwUGEHr5
Hold on. I think I see the problem. It looks like their is a miscommunication, but it looks like part of the problem is you misunderstanding how MtGox works.
First, 1PZmRkTrBv8sSn1mgYtjeVwJLtxwUGEHr5 is not an "account", it's a bitcoin address. Calling it an account just increases the confusion.
Next, MtGox does not hold everyone's bitcoins in segregated addresses, just like when you deposit cash into a bank they don't mark those specific bills as yours and return them to you when you withdraw. MtGox provides you in their user interface with an address that you can use to fund your account. When they see funds arrive at that address, they know that your account should be credited. Then those funds are swept from that "funding" address to other addresses where they are pooled with all the other bitcoins MtGox has received from everyone else.
When you "withdraw" funds from MtGox, they don't send them to you from your funding address. They just take a random address from their pooled funds and send you some bitcoins from there. There is no link created in their database from that address to your account specifically. Sending funds to an address that you've received funds from is generally a bad idea and with MtGox, it is always a bad idea.
So, you may have to explain your issue to MtGox a bit differently to collect your funds.
Keep in mind that anyone could have accidentally sent funds to the address 1PZmRkTrBv8sSn1mgYtjeVwJLtxwUGEHr5, and since it isn't linked specifically to your account in their database and has never shown up in the user interface as a funding address for you, MtGox has to be careful not to give you bitcoins that belong to someone else. I could contact them right now and tell them that I accidentally sent to the wrong address, and that those are my bitcoins (as could anyone else who is reading this forum). They'll want/need to be sure that you actually are the right person to give those bitcoins to before they update your account.
Try contacting them again. This time explain it something like this:
"I've just realized that I used an incorrect address when attempting to fund (deposit into) my account. Rather than sending bitcoins to one of the "funding addresses" that MtGox provides, I accidentally sent bitcoins to an address that MtGox used when sending me a withdrawl in the past. Can you confirm that MtGox owns the address 1PZmRkTrBv8sSn1mgYtjeVwJLtxwUGEHr5? If so, can you please credit the 3.46700611 bitcoins from transaction 929ef144e5c7e439684d6f1f9ef86b332546794dcbaaaf61b3f365b72b0894b0 to my account: M90407683X. I apologize for any inconvenience, and will be more careful about funding my account in the future. I can provide a signature from address 1GwPaTHi6s3XkzaFQe7DwFJNXfmUTbRkiQ to prove that I was the person who sent those bitcoins if necessary."
As I hope you understand now, this is not true.
As you can hopefully see now, the problem isn't in their database. The problem is that with bitcoin you can never assume that an address that you receive bitcoins "from" is a good address to send bitcoins "to".