Maybe my explanation bit stupid but want to share my thoughts on this post. Why someone want to set a mail roles " Dedicated & Everyone " since HC provide option to handle mail services in the hosting plan manager.
 
If you problem resolve by setting both mail server using Everyone role then what's the issue in setting this ? 
For example
First mail server = Exchange 2010
Second Mail Server = Smarter mail
 
Reseller A let say dedicated reseller and you want it for exchange hosting only then just sell him the plan which has exchange role.
 
Reseller B: you want to allow both mail servers then simply sell him 2 plans which include both mail roles.
 
I hope this is the right explanation :)

patrick

@Agermose , I don't know what actually going on with you and HC support. But in my opinion in professional communication specially via email/letter someone shouldn't be using slang words specially F. U. C. K.

Yeah if you are making communication with buddies then we can only use lose talking :)

Agree 

well, totally agree but im not very sorry. From the 364 emails send to support I have in TWO emails used the frase "f... kidding" and "half of brain". Both emails lately after stressing after 1) this issue and 2) an other where it again took more than a week to convince HC support something was wrong.
Of the 364 emails I will be happy to spend an hour tomorrow to count how many are on reporting bugs that for the most part end up beeing accepted as bugs and fixed, and how few are related to feature request or usage questions.
 
so lets just stop trying to paint a picture that Im a big spender of abusive language or anything like this.
 
but I agree of cause on the non usage of abusive language.

its correct that there is a sendmail role on the dedicated server - one not used. The reason they are there at all is because it cannot be disabled anymore.
 
We are not running sendmail at all anymore but mailenable. The reseller plans and the webadmin plans are all mailenable plan.
 
All, EVERYTING, servers and so on are setup by HC. EVERYTHING is setup per HC support directions and EVERY setting is set how You set it - so you will be happy to hear it was working. So something changed. 
 
And if I one day get a mail saying "ok, we now agree it should be working" and the next "but you and your reseller/user will have to wait 6 month / 2 builds for a "maybe fix", then Im sorry to say, you must be kidding :|
 

You can easily remove the Sendmail role from cluster ;), If you remove associated mail domain (sendmail) record from tblMailDomains then sure you can remove the role.
 
What if you set sendmail role to 'Everyone' then can reseller create mails in Mail enable ?

@agermose Did this ever get resolved for you?
 
We have recently purchased HC and we just hit this wall where it would appear you cannot assign a server/role to a reseller. Its kind of a deal breaker for us as that is how we operate!