diff --git a/inc/caldav-REPORT-calquery.php b/inc/caldav-REPORT-calquery.php
index 0c4228c1..4bdf7f9a 100644
--- a/inc/caldav-REPORT-calquery.php
+++ b/inc/caldav-REPORT-calquery.php
@@ -88,7 +88,7 @@ function SqlFilterFragment( $filter, $components, $property = null, $parameter =
     $not_defined = "";
     switch( $tag ) {
       case 'urn:ietf:params:xml:ns:caldav:is-not-defined':
-        $not_defined = "not-"; // then fall through to IS-DEFINED case
+        $not_defined = "not"; // then fall through to IS-DEFINED case
       case 'urn:ietf:params:xml:ns:caldav:is-defined':
         if ( isset( $parameter ) ) {
           $need_post_filter = true;
@@ -114,7 +114,7 @@ function SqlFilterFragment( $filter, $components, $property = null, $parameter =
             default:
               $property_defined_match = "LIKE '_%'";  // i.e. contains a single character or more
           }
-          $sql .= sprintf( "AND %s %s%s ", $property, $not_defined, $property_defined_match );
+          $sql .= sprintf( "AND %s %s %s ", $property, $not_defined, $property_defined_match );
         }
         break;