diff --git a/src/corelib/time/qtimezonelocale_p.h b/src/corelib/time/qtimezonelocale_p.h
index 50e9fc37ef0..18c147c9b50 100644
--- a/src/corelib/time/qtimezonelocale_p.h
+++ b/src/corelib/time/qtimezonelocale_p.h
@@ -35,6 +35,6 @@ namespace QtTimeZoneLocale {
 #if QT_CONFIG(icu)
 QString ucalTimeZoneDisplayName(UCalendar *ucal, QTimeZone::TimeType timeType,
                                 QTimeZone::NameType nameType,
-                                const QString &localeCode);
+                                const QByteArray &localeCode);
 #else
 // Define data types for QTZL_data_p.h
diff --git a/src/corelib/time/qtimezoneprivate_icu.cpp b/src/corelib/time/qtimezoneprivate_icu.cpp
index d992ebfc3aa..f42ffe07678 100644
--- a/src/corelib/time/qtimezoneprivate_icu.cpp
+++ b/src/corelib/time/qtimezoneprivate_icu.cpp
@@ -149,7 +149,7 @@ static QTimeZonePrivate::Data ucalTimeZoneTransition(UCalendar *m_ucal,
     QTimeZone::TimeType timeType = dst == 0 ? QTimeZone::StandardTime : QTimeZone::DaylightTime;
     using namespace QtTimeZoneLocale;
     tran.abbreviation = ucalTimeZoneDisplayName(m_ucal, timeType,
-                                                QTimeZone::ShortName, QLocale().name());
+                                                QTimeZone::ShortName, QLocale().name().toUtf8());
     return tran;
 }
 #endif // U_ICU_VERSION_SHORT
@@ -258,7 +258,7 @@ QString QIcuTimeZonePrivate::displayName(QTimeZone::TimeType timeType,
     // Technically this may be suspect, if locale isn't QLocale(), since that's
     // what we used when constructing m_ucal; does ICU cope with inconsistency ?
     using namespace QtTimeZoneLocale;
-    return ucalTimeZoneDisplayName(m_ucal, timeType, nameType, locale.name());
+    return ucalTimeZoneDisplayName(m_ucal, timeType, nameType, locale.name().toUtf8());
 }
 
 int QIcuTimeZonePrivate::offsetFromUtc(qint64 atMSecsSinceEpoch) const