mail & centos07

hello -

i have been running centOS-6 for some time now. whenever i issue a mailx command from the command line such as this:

echo ‘Subject: testing’ | mailx -v -s ‘this is a test’;

i get a lot of good diagnostic messages such as:

this,is,a,test,-s, Connecting to [] via relay...
220 ESMTP Postfix
>>> EHLO
250-SIZE 10240000

however, on centOS-7 i am not seeing the same verbose messages, even with identical mailx command line. all i am seeing is this:

Mail Delivery Status Report will be mailed to <>.

in both servers (centOS-6 & 7) the email is indeed coming through successfully.

any suggestions will be most appreciated.