Clear recently used documents permanently in KDE4

To do this: 
 solution: type in terminal 
 rm ~/.kde4/share/apps/RecentDocuments/*  
 chmod 000 ~/.kde4/share/apps/RecentDocuments 
 The first line will clear the directory where the shortcuts to the
recent files would be stored 
 The second line will make the directory where the shortcuts to the
recent files would be stored, non-writable, so no history is
recorded...