Hi i have Raq3

i have problems wiht the email aliases when i put

13 characates like this

nazario.orozco@domain.com.mx

he can send ok but if i replay to him it say this

did not reach the following recipient(s):

nazario.orozco@domain.com.mx on Tue, 8 Feb 2005 11:43:07 -0800
The e-mail account does not exist at the organization this message
was sent to. Check the e-mail address, or contact the recipient
directly to find out the correct address.
<mserver.computecmxl #5.1.1 smtp;550 5.1.1
<nazario.orozco@domani.com.mx>... User unknown>

the other i have email aliases under 11 and works 100% the problem is up 12 it say does not exit the email any ideas

thkx in advance :)