E-Mail Receive problem from special domain

i use ISPconfig 2.2.14 on a centos5 perfect install. everything seems to be working. i get emails and could send emails. during testing we see that we can´t get emails from domain "www.xyz.de". sending emails to it is ok. i put that domain on the whitelist but no effect.

any idea ?

 

sorry, my fault - it´s now working, was a problem at the sending email server.

thanks anyway !