diff --git a/toplevel.cpp b/toplevel.cpp
index f7be70bb25..3b3d6895db 100644
--- a/toplevel.cpp
+++ b/toplevel.cpp
@@ -154,7 +154,7 @@ void Toplevel::getWindowRole()
 /*!
   Returns SM_CLIENT_ID property for a given window.
  */
-QByteArray Toplevel::staticSessionId(WId w)
+QByteArray Toplevel::staticSessionId(xcb_window_t w)
 {
     return getStringProperty(w, atoms->sm_client_id);
 }
@@ -162,9 +162,9 @@ QByteArray Toplevel::staticSessionId(WId w)
 /*!
   Returns WM_COMMAND property for a given window.
  */
-QByteArray Toplevel::staticWmCommand(WId w)
+QByteArray Toplevel::staticWmCommand(xcb_window_t w)
 {
-    return getStringProperty(w, XA_WM_COMMAND, ' ');
+    return getStringProperty(w, XCB_ATOM_WM_COMMAND, ' ');
 }
 
 /*!
diff --git a/toplevel.h b/toplevel.h
index 8c12ec58b6..5caf08ceab 100644
--- a/toplevel.h
+++ b/toplevel.h
@@ -385,8 +385,8 @@ protected:
     bool m_isDamaged;
 
 private:
-    static QByteArray staticSessionId(WId);
-    static QByteArray staticWmCommand(WId);
+    static QByteArray staticSessionId(xcb_window_t);
+    static QByteArray staticWmCommand(xcb_window_t);
     static xcb_window_t staticWmClientLeader(xcb_window_t);
     // when adding new data members, check also copyToDeleted()
     Window client;