Search Builder and preferred communication method

FIling issue as per forum post http://forum.civicrm.org/index.php?topic=23004.0

Seems to be a bug when creating a query and setting the Preferred Communication Method value to IS NULL or IS NOT NULL

Steps to reproduce:
Select Search Builder
Include contacts where record type = "contact"
Field "Preferred Communication Method" and "IS NULL"
Perform the search

Error: Sorry but we are not able to provide this at the moment.
DB Error: syntax error

Going back I get this warning
Warning: implode(): Invalid arguments passed in CRM_Contact_BAO_Query->preferredCommunication() (line 3778 of /var/www/drupal7.civicrm.org/svn/civicrmdemo43/CRM/Contact/BAO/Query.php).

Have tested on sandbox 4.4 and can reproduce.

Thanks,
Maya