Ok I recently purchased a BB Pearl from someone. The person told me it was fully unlocked an pin free.

Now today I activated the BIS when:

I realize there is already an email account on the fone registered at yahoo an I am currently receiving myspace messages for the email address. I called the person an they told me they got the fone from over seize an they didnt know that a BIS had been active on the phone before.

The phone says T- Mobile at the bottom so I guess it was previously on T- Mobile's Network

Is there any way of getting rid of this email account?

You might try calling your carrier and explaining the situation and see if they can get the old BIS account closed so you can use your PIN and IMEI to set up a new one. Some will help, others will not/cannot.

Otherwise, try to return it and get your money back.

I agree to call the carrier