I have my Joomla installation in a subdirectory which is transparently supported by the "live_site" config variable.
The live site is accessible here:
www.lsp.hu
Joomla actually lives here:
www.lsp.hu/content
The redirection is done by htaccess url rewrite. All pages including images are served, and their url doesn't contain the "/content/" part - just as expected.
Now, with MJ Domains, every link, including image references, do have the "/content/" part, which breaks the transparent redirection. Seems like MJ ignores the "live_site" config variable. This only happens with mobile subdomains (e.g. mobile.mysite.com), not when using the main domain.