Right way to use piwik for a multi-domain hosted website

I’m hosting a website on 2 different servers under two different domains.
Currently I’ve installed piwik on domain A. Piwik’s tracking script is included on both websites (domain A / domain B).
Inside piwik configuration I’ve created one website with 2 URLs (Damain A and Domain B).

Is this the right way to use piwik in such a setup?
Are threre problems regarding cross-domain-cookies (espacially in IE)?
Or is there another method to achive one merged statistic for both domains?

Thanks.

this is a correct way of tracking 2 websites in 1 piwik install