Disabling a "related contact" relationship should "un-relate" the contact

Created based on http://forum.civicrm.org/index.php/topic,18841

If there are 2 relationships between contacts A and B, but only one gives A "related contact" access to B, then if the relationship which gives that access is disabled, contact A still has access to B.

Steps to reproduce on 3.4 sandbox ...

• Go to contact summary for an Individual
• Create relationship "Head of Household for" "Alan Smith's home"
• Create relationship "Household Member of" "Alan Smith's home" (setting it so the Individual contact can see and edit the Household)
• Show Individual's Contact Dashboard - can see Household
• Go back to Contact Summary and disable relationship "Household Member of"
• Go back to Individual's Contact Dashboard and "Alan Smith's home" is still accessible

( My guess is the program logic is saying "yes there's an enabled relationship" and "yes, there's a related-contact relationship" but not realising they are different relationships. )

Perhaps a related issue, but after taking these steps I get the following errors ...

Fatal error: CRM_Contact_Form_RelatedContact::require_once() [function.require]: Failed opening required 'CRM/Contact/Form/Household.php' (include_path='/var/www/drupal.civicrm.org/svn/civicrm34/tools/drupal/modules/civicrm_regsite/:.:/var/www/sandbox.civicrm.org/public/sites/sandbox.civicrm.org/modules/civicrm/:/var/www/sandbox.civicrm.org/public/sites/sandbox.civicrm.org/modules/civicrm//packages:.:/usr/share/php:/usr/share/pear') in /var/www/drupal.civicrm.org/svn/civicrm34/CRM/Contact/Form/RelatedContact.php on line 185