[Andreas]

OK, this is just spin-off and untested

In memberlist.php FIND

PHP Code:

'usergroupid' => INT 


REPLACE that with

PHP Code:

'usergroupid' => INT,
'haspic' => INT 


FIND

PHP Code:

if ($vboptions['usememberlistadvsearch'])
{ 


BELOW that ADD

PHP Code:

if ($haspic) {
  $condition .= " AND NOT ISNULL(customprofilepic.userid) ";
} 


FIND

PHP Code:

$userscount = $DB_site->query_first("
        SELECT COUNT(*) AS users
        FROM " . TABLE_PREFIX . "user AS user
        LEFT JOIN " . TABLE_PREFIX . "userfield AS userfield USING (userid)
        WHERE $condition
                AND     user.usergroupid IN ($ids)
"); 


REPLACE that with

PHP Code:

$userscount = $DB_site->query_first("
        SELECT COUNT(*) AS users
        FROM " . TABLE_PREFIX . "user AS user
        LEFT JOIN " . TABLE_PREFIX . "userfield AS userfield USING (userid)
        " . iif($haspic, "LEFT JOIN " . TABLE_PREFIX . "customprofilepic AS customprofilepic ON (customprofilepic.userid=user.userid)") . "
        WHERE $condition
                AND     user.usergroupid IN ($ids)
"); 


FIND

PHP Code:

" . iif($show['profilepiccol'], "LEFT JOIN " . TABLE_PREFIX . "customprofilepic AS customprofilepic ON (user.userid = customprofilepic.userid) ") . " 


REPLACE that with

PHP Code:

" . iif($show['profilepiccol'] OR $haspic, "LEFT JOIN " . TABLE_PREFIX . "customprofilepic AS customprofilepic ON (user.userid = customprofilepic.userid) ") . " 


In Template memberlist_search create a checkbox named haspic with value 1 (whereever you want to have it):

<label for="cb_haspic"><input type="checkbox" name="haspic" value="1" id="cb_haspict" />Show only members who have a profile picture</label>

... I think that's it.