diff --git a/libkwineffects/anidata.cpp b/libkwineffects/anidata.cpp
index 3bb970f550..f1a07d46cb 100644
--- a/libkwineffects/anidata.cpp
+++ b/libkwineffects/anidata.cpp
@@ -29,7 +29,7 @@ AniData::AniData()
 {
     attribute = AnimationEffect::Opacity;
     windowType = (NET::WindowTypeMask)0;
-    duration = time = meta = 0;
+    duration = time = meta = startTime = 0;
     waitAtSource = false;
 }
 
@@ -37,7 +37,6 @@ AniData::AniData(AnimationEffect::Attribute a, int meta, int ms, const FPx2 &to,
                  QEasingCurve curve, int delay, const FPx2 &from, bool waitAtSource )
 {
     attribute = a;
-    startTime = QTime::currentTime().addMSecs(delay);
     this->from = from;
     this->to = to;
     this->curve = curve;
@@ -45,6 +44,7 @@ AniData::AniData(AnimationEffect::Attribute a, int meta, int ms, const FPx2 &to,
     time = 0;
     this->meta = meta;
     this->waitAtSource = waitAtSource;
+    startTime = AnimationEffect::clock() + delay;
 }
 
 AniData::AniData(const AniData &other)
@@ -54,11 +54,11 @@ AniData::AniData(const AniData &other)
     to = other.to;
     time = other.time;
     duration = other.duration;
-    startTime = other.startTime;
     curve = other.curve;
     customCurve = other.customCurve;
     windowType = other.windowType;
     meta = other.meta;
+    startTime = other.startTime;
 }
 
 static FPx2 fpx2(const QString &s, AnimationEffect::Attribute a)
diff --git a/libkwineffects/anidata_p.h b/libkwineffects/anidata_p.h
index 33d8c03da2..df4e088b58 100644
--- a/libkwineffects/anidata_p.h
+++ b/libkwineffects/anidata_p.h
@@ -23,7 +23,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "kwinanimationeffect.h"
 #include <QEasingCurve>
-#include <QTime>
 #include <netwm.h>
 
 namespace KWin {
@@ -47,7 +46,7 @@ public:
     FPx2 from, to;
     int time, duration;
     uint meta;
-    QTime startTime;
+    qint64 startTime;
     NET::WindowTypeMask windowType;
     bool waitAtSource;
 };
diff --git a/libkwineffects/kwinanimationeffect.cpp b/libkwineffects/kwinanimationeffect.cpp
index 0e126dca4b..e0a66941b1 100644
--- a/libkwineffects/kwinanimationeffect.cpp
+++ b/libkwineffects/kwinanimationeffect.cpp
@@ -21,10 +21,13 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "kwinanimationeffect.h"
 #include "anidata_p.h"
 
-#include <QTime>
+#include <QDateTime>
 #include <QTimer>
 
 namespace KWin {
+
+QElapsedTimer AnimationEffect::s_clock;
+
 struct AnimationEffectPrivate {
 public:
     AnimationEffectPrivate() { m_animated = m_damageDirty = false; }
@@ -40,6 +43,8 @@ AnimationEffect::AnimationEffect() : d_ptr(new AnimationEffectPrivate())
 {
     Q_D(AnimationEffect);
     d->m_animated = false;
+    if (!s_clock.isValid())
+        s_clock.start();
     /* this is the same as the QTimer::singleShot(0, SLOT(init())) kludge
      * defering the init and esp. the connection to the windowClosed slot */
     QMetaObject::invokeMethod( this, "init", Qt::QueuedConnection );
@@ -202,7 +207,7 @@ void AnimationEffect::prePaintScreen( ScreenPrePaintData& data, int time )
         bool invalidateLayerRect = false;
         QList<AniData>::iterator anim = entry->first.begin(), animEnd = entry->first.end();
         while (anim != animEnd) {
-            if (QTime::currentTime() < anim->startTime) {
+            if (anim->startTime > clock()) {
                 if (!anim->waitAtSource) {
                     ++anim;
                     continue;
@@ -347,7 +352,7 @@ void AnimationEffect::prePaintWindow( EffectWindow* w, WindowPrePaintData& data,
         if ( entry != d->m_animations.constEnd() ) {
             bool isUsed = false;
             for (QList<AniData>::const_iterator anim = entry->first.constBegin(); anim != entry->first.constEnd(); ++anim) {
-                if (QTime::currentTime() < anim->startTime && !anim->waitAtSource)
+                if (anim->startTime > clock() && !anim->waitAtSource)
                     continue;
 
                 isUsed = true;
@@ -392,7 +397,7 @@ void AnimationEffect::paintWindow( EffectWindow* w, int mask, QRegion region, Wi
         if ( entry != d->m_animations.constEnd() ) {
             for ( QList<AniData>::const_iterator anim = entry->first.constBegin(); anim != entry->first.constEnd(); ++anim ) {
 
-                if (QTime::currentTime() < anim->startTime && !anim->waitAtSource)
+                if (anim->startTime > clock() && !anim->waitAtSource)
                     continue;
 
                 switch (anim->attribute) {
@@ -511,14 +516,14 @@ void AnimationEffect::postPaintScreen()
 
 float AnimationEffect::interpolated( const AniData &a, int i ) const
 {
-    if (QTime::currentTime() < a.startTime)
+    if (a.startTime > clock())
         return a.from[i];
     return a.from[i] + a.curve.valueForProgress( ((float)a.time)/a.duration )*(a.to[i] - a.from[i]);
 }
 
 float AnimationEffect::progress( const AniData &a ) const
 {
-    if (QTime::currentTime() < a.startTime)
+    if (a.startTime > clock())
         return 0.0;
     return a.curve.valueForProgress( ((float)a.time)/a.duration );
 }
@@ -630,7 +635,7 @@ void AnimationEffect::updateLayerRepaints()
         QList<QRect> rects;
         QRect *layerRect = const_cast<QRect*>(&(entry->second));
         for (QList<AniData>::const_iterator anim = entry->first.constBegin(), animEnd = entry->first.constEnd(); anim != animEnd; ++anim) {
-            if (QTime::currentTime() < anim->startTime)
+            if (anim->startTime > clock())
                 continue;
             switch (anim->attribute) {
                 case Opacity:
diff --git a/libkwineffects/kwinanimationeffect.h b/libkwineffects/kwinanimationeffect.h
index 2ffaa22184..76a5b9b504 100644
--- a/libkwineffects/kwinanimationeffect.h
+++ b/libkwineffects/kwinanimationeffect.h
@@ -22,6 +22,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define ANIMATION_EFFECT_H
 
 #include <QEasingCurve>
+#include <QElapsedTimer>
 #include <QtCore/qmath.h>
 #include <kwineffects.h>
 
@@ -139,6 +140,10 @@ public:
         return qExp(progress);
     }
 
+    static inline qint64 clock() {
+        return s_clock.elapsed();
+    }
+
 protected:
     /**
      * The central function of this class - call it to create an animated transition of any supported attribute
@@ -177,6 +182,7 @@ private Q_SLOTS:
     void _windowDeleted( KWin::EffectWindow* w );
     void _expandedGeometryChanged(KWin::EffectWindow *w, const QRect &old);
 private:
+    static QElapsedTimer s_clock;
     typedef QMap< EffectWindow*, QPair<QList<AniData>, QRect> > AniMap;
     AnimationEffectPrivate * const d_ptr;
     Q_DECLARE_PRIVATE(AnimationEffect)