Problem with internal mail

hello to all, first sorry for me english and thanks for the help

my problem is this

there is 1 server with 8.0.1 in 2003 server

i configure the server to receive mail from two different internet domain

abc.es

def.com

well, this work perfect and the primary domain is abc.es

i want that when i send a mail to user1@def.com, if the user not exist in def.com dont search in abc.es but it seem to be imposible with the global domain document

i try change the address lookup in the server configuration; router/smtp tab; basic; and set address lookup to fullname only

there, if send a mail to user1@def.com, if it not exist, it search user1@def.com in the primary domain, but it not exist because it search user1@def.com, the complete string

this is my idea, but when i change this parameter, the people cant send mail to the internal user of the domain, when they send a mail looking the people in the dominy directory, the mail is sent to the <full name/domain@internet domain>

for example, if my mail is afernandez@abc.es and i try to send a message from other person of the company, the mail send to Alberto Fernandez Caballero/ABC@ABC.es not to afernandez@abc.es, for this, it search the complete string and dont find this is the domain

please, how i can change this and when i send a mail from the internal domain, it will be send to the afernandez@abc.es

thanks to all

Subject: Help

nobody have any idea???

please, help me with this problem