diff --git a/calendar/edit_entry.php b/calendar/edit_entry.php
index 6fc5d3744d..ca1588b259 100755
--- a/calendar/edit_entry.php
+++ b/calendar/edit_entry.php
@@ -282,7 +282,7 @@
 	@reset($users);
 	while ($user = each($users))
 	{
-		if($user[0] != $owner && $phpgw->accounts->exists($user[0]) == True)
+		if($user[0] != $owner && $phpgw->accounts->exists(intval($user[0])) == True)
 		{
 			$str .= '    <option value="' . $user[0] . '"'.$parts[$user[0]].'>('.$phpgw->accounts->get_type($user[0]).') '.$user[1].'</option>'."\n";
 		}
diff --git a/phpgwapi/inc/class.accounts_ldap.inc.php b/phpgwapi/inc/class.accounts_ldap.inc.php
index 0415180acf..e83759526c 100644
--- a/phpgwapi/inc/class.accounts_ldap.inc.php
+++ b/phpgwapi/inc/class.accounts_ldap.inc.php
@@ -219,9 +219,9 @@
 			if (gettype($account_id) == "string") {
 				$account_id = $this->name2id($account_id);
 			}
-			$sql = "SELECT account_id FROM phpgw_accounts WHERE account_id='".$account_id."'";
+			$sql = "SELECT account_id FROM phpgw_accounts WHERE account_id=".$account_id;
 			$this->db->query($sql,__LINE__,__FILE__);
-			if ($this->db->num_rows()) {
+			if ($this->db->num_rows() == 1) {
 				return True;
 			} else {
 				return False;