Fatal error when using it as maintenance theme :
Fatal error: Call to undefined function node_get_types() in
The solution in my opinion in is to use another condition.
I tried !defined('MAINTENANCE_MODE') which seems to be a standard way but it doesn't work because Drupal tries to load all files before starting its core functions.
Then i tried this module_exists('menu') and it did the trick. finally i thought that it's much safer to use function_exists('node_get_types').
There was also a warning after which has been take care of in this patch.
Warning: in_array() [function.in-array]: Wrong datatype for second argument in site\sina\sites\all\themes\acquia_marina\template.php on line 164
I attached the patch. please have look.