Why "include_dir" and "ebin_dir" cannot be put into a server declaration like that ?

<server www.sample.com>
 doc_root = "/var/www/sample"
 include_dir = "include/"
 ebin_dir = "ebin/"

the directories 'include' and 'ebin' are relative to 'doc_root'.

An another problem I have is the name collision into two modules which theires names are the same, I have to prefix each module by the name of his website. Is there an another solution ?