diff --git a/kcontrol/keyboard/xkb_rules.cpp b/kcontrol/keyboard/xkb_rules.cpp
index 550f8fd0..d6ffad3e 100644
--- a/kcontrol/keyboard/xkb_rules.cpp
+++ b/kcontrol/keyboard/xkb_rules.cpp
@@ -142,7 +142,7 @@ QString Rules::getRulesName()
 		return name;
 	}
 
-	return QString::null;
+	return QString();
 }
 
 static QString findXkbRulesFile()
diff --git a/libs/kdm/kgreet_generic.cpp b/libs/kdm/kgreet_generic.cpp
index 3fb3459e..4539af4d 100644
--- a/libs/kdm/kgreet_generic.cpp
+++ b/libs/kdm/kgreet_generic.cpp
@@ -296,7 +296,7 @@ KGenericGreeter::clear()
 {
     // assert(!running && !passwd1Edit);
     revive();
-    curUser = QString::null;
+    curUser = QString();
 }
 
 
diff --git a/libs/ksysguard/processcore/processes.cpp b/libs/ksysguard/processcore/processes.cpp
index 6c5dcaea..b7805c4d 100644
--- a/libs/ksysguard/processcore/processes.cpp
+++ b/libs/ksysguard/processcore/processes.cpp
@@ -522,7 +522,7 @@ bool Processes::loadHistoryFile(const QString &filename)
 QString Processes::historyFileName() const
 {
     if(!d->mIsLocalHost || !d->mHistoricProcesses)
-        return QString::null;
+        return QString();
     return d->mHistoricProcesses->historyFileName();
 }
 QDateTime Processes::viewingTime() const
diff --git a/libs/ksysguard/processcore/processes.h b/libs/ksysguard/processcore/processes.h
index 7023cc8b..9cae19d8 100644
--- a/libs/ksysguard/processcore/processes.h
+++ b/libs/ksysguard/processcore/processes.h
@@ -56,7 +56,7 @@ namespace KSysGuard
 
     public:
 
-        Processes(const QString &hostname = QString::null, QObject * parent = 0);
+        Processes(const QString &hostname = QString(), QObject * parent = 0);
         virtual ~Processes();
         enum UpdateFlag {
             StandardInformation = 1,