more then one entry in Web mail MTA Hostnames: ?

[sadiq007]

Hi,
My primary domain1.com is working fine.Now i just added secondary domain2.com into same server , while sending mail from both domain the SMTP header showing Received FROM: mail.domain1.com ( primary domain1.com's MX) (is it ok?)
but after adding secondary domain2.com's MX mail.domain2.com into
Admin Panel > Servers > MTA > Web mail MTA Hostnames:
so now Web mail MTA Hostnames: have two entries mail.domain1.com and mail.domain2.com ( can i have more then one hostnames?)
After this if now i am sending mail from domain1.com then SMTP banners having mail.domain1.com and sending mail from domain2.com it will showing mail.domain2.com in LAST Received From: header and other Received From: having still mail.domain1.com ( is this correct )

As my domain1.com is for regular mailing and domain2.com is for bulk mailing so i don't want that domain2.com will create any problem for domain1.com