As i already mentioned: GLPI is just a Webapplication. The only thing you need is a Webserver with PHP and a MySQL-Server. If you have this running on your Solaris Machine it should not be a problem to running GLPI on that.
It does not look like GLPI supports MS-SQL, but as it is only a PHP-Application you can download it and change the database connection to MS-SQL if you know how to program PHP.
Here you can find the GLPI Documentation: http://glpi-project.org/spip.php?rubrique18