Calguys User Directory - Error

[hgmd2005]

DEBUG: error in count query
QUERY = SELECT count(U.id) FROM site1_cms_module_feusers_users U LEFT JOIN site1_cms_module_feusers_belongs bel ON U.id = bel.userid LEFT JOIN site1_cms_module_feusers_properties P ON U.id = P.userid WHERE bel.groupid = '3' AND expires > '2011-06-30 22:15:03' AND P.title = 'lastname' AND P.data LIKE 'Y%'
Error =
Warning: Invalid argument supplied for foreach() in /home/content/03/7321103/html/_clients/dickinsonisdalumni.com/lib/content.functions.php(975) : eval()'d code on line 17

Issue found here.. When the display shows the Letters it will show Letters of fields that are empty and I get the above error..

This is Members group, but NO "Y" lastnames.. it shows a link to Y, but it creates this error, the link to Y shouldn't even be selectable.

This is in the Template
{CGUserDirectory group="Members" action="directory" summarytemplate="Member-List-Test" prop="lastname" pagelimit="100" sortorder="ASC"}