I doubt we'll get $this->hookError set to '0', but let's head that off at the pass.

diff --git a/includes/EditPage.php b/includes/EditPage.php
index c26b633..ddd49e7 100644 (file)
--- a/includes/EditPage.php
+++ b/includes/EditPage.php
@@ -1037,7 +1037,7 @@ class EditPage {
                                $wgOut->addWikiText( '<div id="mw-missingcommentheader">' . wfMsg( 'missingcommentheader' ) . '</div>' );
                        }
 
-                       if( $this->hookError ) {
+                       if( $this->hookError !== '' ) {
                                $wgOut->addWikiText( $this->hookError );
                        }