diff --git a/clients/b2/b2client.cpp b/clients/b2/b2client.cpp
index e26a9d6553..cd74ef778b 100644
--- a/clients/b2/b2client.cpp
+++ b/clients/b2/b2client.cpp
@@ -131,7 +131,7 @@ static void delete_pixmaps()
 }
 
 
-B2Button::B2Button(Client *_client=0, QWidget *parent=0, const QString& tip=NULL)
+B2Button::B2Button(Client *_client, QWidget *parent, const QString& tip)
    : KWinButton(parent, 0, tip) 
 { 
     setBackgroundMode(NoBackground);