Mail problem

[vlados]

Hello
I have a problem sending mails. Postfix retuns:
Dec 11 08:49:28 srv01 postfix/error[11127]: 165225C484: to=<vlados.01@gmail.com>, relay=none, delay=0.07, delays=0.02/0.03/0/0.03, dsn=4.3.5, status=deferred (delivery temporarily suspended: mail for netlabs.bg loops back to myself)

vladislav@srv01:~$ host netlabs.bg
netlabs.bg has address 78.90.82.221
netlabs.bg mail is handled by 1 ns2.netlabs.bg.
vladislav@srv01:~$ host ns2.netlabs.bg
ns2.netlabs.bg has address 78.90.82.89
vladislav@srv01:~$

What i did wrong?