I want to use zohomail as mu email server.

I have three domains... email@domain1.com is already setup as a maillist subscription and working perfectly. It is setup so that anything sent to domain.com goes into that mailbox as a catchall

I have two more domain I would like an email address setup as using the same idea. so @domain2 and @Anonymous User 

If I try to add a subscription. it only allows me to "upgrade" my current subscription. I can add domains to my current subscription and add the address to my original maillite subscription and each does have its own username and password to set up in my mail client (Macmail)... but I get all emails for every domain in each mailbox...

I just want to pay for three subscriptions and manage them separately under one account. Is that possible because I cant work it out? 

I could create a completely new ZohoMail account with separate logins for each but they it's unwieldy...

Is this possible?