Drupal Single Sign On same installation

Avg Bid (EUR)
Project Budget (EUR)
€30 - €250

Project Description:
I have a Drupal 7 installation with the domain access module installed.
This installation i have connected many domains with different theme, but basically they have the same core and the same database.

The problem is that the domain access module support the single sign on only on subdomain and not on primary domain (domain cookie stuff).

What i need is a code/module that implement the single sign on, so if i login to the domain1.com im logged in also into domain2.com.
Basically i think that this problem could be solved generating the cookie for the list of the domain installed on Drupal, but i'm not sure.

Additional Project Description:
03/22/2013 at 0:09 IST
mayeb i wasnt clear enought, domain1 and domain2 are the same drupal installation. domain1.com point to domain2 to

Skills required:
Drupal, MySQL, PHP
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