are multiple sites really necessary ?
I am currently working on a site in 3 languages with the text content maintained using powercms builder
I do not have separate sites, i have the language set using a session variable and a PHP case statement which inserts the appropriate language content based on the session variable. All of the content is managed within a single instance of power cms for example for the home page, i have sections called content-english, content-dutch and content-greek. Seems to work well.
If you are interested i can post some code