Well , i solved the issue .
Basically and because it is not explained in iredmail , when this happens the first thing to do is to check the mail.log to see what happened .
this case it was :
tail -f /var/log/mail.log

At first i notice that postfix was rejecting the emails because of the hostname of the sender .
It looks that postfix looks for that hostname of the sender before get in thru .
I solved that on settings in main.cf

then after that i got a new block error that was telling me something about errors in the Helo command from the sender , witch is basically the first this that an email server says to another before starting sending the emails .

Stuff changed in the main.cf to make this work and also from searches on the web from the issues i found .

smtpd_helo_required = yes
smtpd_helo_restrictions =
    permit_mynetworks
    permit_sasl_authenticated
   # check_helo_access pcre:/etc/postfix/helo_access.pcre (in here postfix looks a set of rules)
    #reject_non_fqdn_helo_hostname
   # reject_unknown_helo_hostname
     reject_invalid_helo_hostname

smtpd_sender_restrictions =
    reject_unknown_sender_domain
    #reject_non_fqdn_sender
    #reject_unlisted_sender
    permit_mynetworks
    permit_sasl_authenticated
    #check_sender_access pcre:/etc/postfix/sender_access.pcre
    permit

# Recipient restrictions
smtpd_relay_restrictions =
    reject_unknown_recipient_domain
   # reject_non_fqdn_recipient
   # reject_unlisted_recipient
   # check_policy_service inet:127.0.0.1:7777
    permit_mynetworks
    permit_sasl_authenticated
    reject_unauth_destination
    permit

i had to made all these changes to make it work , however i believe that some of them must be reactivated , witch i will do it as soon as i get sometime here , but at least it is working this way .
     permit

here it is the original error :
connect from dellbld07.srv.portugalmail.net[195.170.168.71]
May 29 21:25:23 mail postfix/smtpd[23816]: NOQUEUE: reject: RCPT from dellbld07.srv.portugalmail.net[195.170.168.71]: 450 4.7.1 <a.smtp.portugalmail.pt>: Helo command rejected: Host not found; from=<somemail@portugalmail.pt> to=<myemail@myserver.com> proto=ESMTP helo=<a.smtp.portugalmail.pt>
May 29 21:25:23 mail postfix/smtpd[23816]: disconnect from dellbld07.srv.portugalmail.net[195.170.168.71

Main error was : command rejected: Host not found;

You can add a line in /etc/postfix/helo_access.pcre to bypass this HELO hostname, like this:

/^a\.smtp\.portugalmail\.pt$/ DUNNO

Note: please add this line above other lines. Matched first rule wins.