diff --git a/messagelist/src/core/manager.h b/messagelist/src/core/manager.h
--- a/messagelist/src/core/manager.h
+++ b/messagelist/src/core/manager.h
@@ -23,7 +23,7 @@
 
 #include <core/sortorder.h>
 #include <QList>
-#include <QHash>
+#include <QMap>
 #include <QObject>
 
 #include <collection.h>
@@ -61,8 +61,8 @@
 private:
     static Manager *mInstance;
     QList< Widget * > mWidgetList;
-    QHash< QString, Aggregation * > mAggregations;
-    QHash< QString, Theme * > mThemes;
+    QMap< QString, Aggregation * > mAggregations;
+    QMap< QString, Theme * > mThemes;
     KMime::DateFormatter *mDateFormatter = nullptr;
     QString mCachedLocalizedUnknownText;
 
@@ -102,7 +102,7 @@
     void addAggregation(Aggregation *set);
     void removeAllAggregations();
 
-    const QHash< QString, Aggregation * > &aggregations() const
+    const QMap< QString, Aggregation * > &aggregations() const
     {
         return mAggregations;
     }
@@ -132,7 +132,7 @@
     void addTheme(Theme *set);
     void removeAllThemes();
 
-    const QHash< QString, Theme * > &themes() const
+    const QMap< QString, Theme * > &themes() const
     {
         return mThemes;
     }
diff --git a/messagelist/src/core/manager.cpp b/messagelist/src/core/manager.cpp
--- a/messagelist/src/core/manager.cpp
+++ b/messagelist/src/core/manager.cpp
@@ -128,7 +128,7 @@
     }
 
     // try just the first one
-    QHash< QString, Aggregation * >::ConstIterator it = mAggregations.constBegin();
+    QMap< QString, Aggregation * >::ConstIterator it = mAggregations.constBegin();
     if (it != mAggregations.constEnd()) {
         return *it;
     }
@@ -379,8 +379,8 @@
 
 void Manager::removeAllAggregations()
 {
-    QHash< QString, Aggregation * >::ConstIterator end(mAggregations.constEnd());
-    for (QHash< QString, Aggregation * >::ConstIterator it = mAggregations.constBegin(); it != end; ++it) {
+    QMap< QString, Aggregation * >::ConstIterator end(mAggregations.constEnd());
+    for (QMap< QString, Aggregation * >::ConstIterator it = mAggregations.constBegin(); it != end; ++it) {
         delete(*it);
     }
 
@@ -448,7 +448,7 @@
     }
 
     // try just the first one
-    QHash< QString, Theme * >::ConstIterator it = mThemes.constBegin();
+    QMap< QString, Theme * >::ConstIterator it = mThemes.constBegin();
     if (it != mThemes.constEnd()) {
         return *it;
     }
@@ -807,8 +807,8 @@
 
 void Manager::removeAllThemes()
 {
-    QHash< QString, Theme * >::ConstIterator end(mThemes.constEnd());
-    for (QHash< QString, Theme * >::ConstIterator it = mThemes.constBegin(); it != end; ++it) {
+    QMap< QString, Theme * >::ConstIterator end(mThemes.constEnd());
+    for (QMap< QString, Theme * >::ConstIterator it = mThemes.constBegin(); it != end; ++it) {
         delete(*it);
     }
 
@@ -950,8 +950,8 @@
         conf.writeEntry("Count", mAggregations.count());
 
         int idx = 0;
-        QHash< QString, Aggregation * >::ConstIterator end(mAggregations.end());
-        for (QHash< QString, Aggregation * >::ConstIterator it = mAggregations.constBegin(); it != end; ++it) {
+        QMap< QString, Aggregation * >::ConstIterator end(mAggregations.end());
+        for (QMap< QString, Aggregation * >::ConstIterator it = mAggregations.constBegin(); it != end; ++it) {
             conf.writeEntry(QStringLiteral("Set%1").arg(idx), (*it)->saveToString());
             ++idx;
         }
@@ -966,8 +966,8 @@
         conf.writeEntry("Count", mThemes.count());
 
         int idx = 0;
-        QHash< QString, Theme * >::ConstIterator end(mThemes.constEnd());
-        for (QHash< QString, Theme * >::ConstIterator it = mThemes.constBegin(); it != end; ++it) {
+        QMap< QString, Theme * >::ConstIterator end(mThemes.constEnd());
+        for (QMap< QString, Theme * >::ConstIterator it = mThemes.constBegin(); it != end; ++it) {
             conf.writeEntry(QStringLiteral("Set%1").arg(idx), (*it)->saveToString());
             ++idx;
         }
diff --git a/messagelist/src/utils/configureaggregationsdialog.cpp b/messagelist/src/utils/configureaggregationsdialog.cpp
--- a/messagelist/src/utils/configureaggregationsdialog.cpp
+++ b/messagelist/src/utils/configureaggregationsdialog.cpp
@@ -29,7 +29,7 @@
 #include <QGridLayout>
 #include <QPushButton>
 #include <QFrame>
-#include <QHash>
+#include <QMap>
 
 #include <KLocalizedString>
 #include <KIconLoader>
@@ -258,9 +258,9 @@
     if (!Manager::instance()) {
         return;
     }
-    const QHash< QString, Aggregation * > &sets = Manager::instance()->aggregations();
-    QHash< QString, Aggregation * >::ConstIterator end(sets.constEnd());
-    for (QHash< QString, Aggregation * >::ConstIterator it = sets.constBegin(); it != end; ++it) {
+    const QMap< QString, Aggregation * > &sets = Manager::instance()->aggregations();
+    QMap< QString, Aggregation * >::ConstIterator end(sets.constEnd());
+    for (QMap< QString, Aggregation * >::ConstIterator it = sets.constBegin(); it != end; ++it) {
         (void)new AggregationListWidgetItem(mAggregationList, *(*it));
     }
 }
diff --git a/messagelist/src/utils/configurethemesdialog.cpp b/messagelist/src/utils/configurethemesdialog.cpp
--- a/messagelist/src/utils/configurethemesdialog.cpp
+++ b/messagelist/src/utils/configurethemesdialog.cpp
@@ -29,7 +29,7 @@
 #include <QGridLayout>
 #include <QPushButton>
 #include <QFrame>
-#include <QHash>
+#include <QMap>
 
 #include <KMessageBox>
 #include <KLocalizedString>
@@ -256,10 +256,10 @@
 
 void ConfigureThemesDialog::Private::fillThemeList()
 {
-    const QHash< QString, Theme * > &sets = Manager::instance()->themes();
+    const QMap< QString, Theme * > &sets = Manager::instance()->themes();
 
-    QHash< QString, Theme * >::ConstIterator end(sets.constEnd());
-    for (QHash< QString, Theme * >::ConstIterator it = sets.constBegin(); it != end; ++it) {
+    QMap< QString, Theme * >::ConstIterator end(sets.constEnd());
+    for (QMap< QString, Theme * >::ConstIterator it = sets.constBegin(); it != end; ++it) {
         (void)new ThemeListWidgetItem(mThemeList, *(*it));
     }
 }