diff -Nur xfree86-driver-synaptics-0.99.3.orig/src/synaptics.c xfree86-driver-synaptics-0.99.3/src/synaptics.c
--- xfree86-driver-synaptics-0.99.3.orig/src/synaptics.c	2008-12-15 00:33:15.000000000 +0100
+++ xfree86-driver-synaptics-0.99.3/src/synaptics.c	2009-04-21 16:53:56.000000000 +0200
@@ -124,6 +124,9 @@
 static Bool QueryHardware(LocalDevicePtr);
 static void ReadDevDimensions(LocalDevicePtr);
 
+int oldTimeMillis =0;
+Bool wasTimeSkipped = FALSE;
+
 #if GET_ABI_MAJOR(ABI_XINPUT_VERSION) >= 3
 void InitDeviceProperties(LocalDevicePtr local);
 int SetProperty(DeviceIntPtr dev, Atom property, XIPropertyValuePtr prop,
@@ -1538,6 +1541,57 @@
 	dy += hw->guest_dy;
     }
 
+	/* See if movements are too quick to take
+	   place in few milliseconds
+	 */
+	if (dx || dy) {
+		int oldMillis = priv->move_hist[priv->hist_index].millis;
+		int oldX = priv->move_hist[priv->hist_index].x;
+		int oldY = priv->move_hist[priv->hist_index].y;
+		int elapsed_time = hw->millis - oldMillis;
+		int dX = abs(abs(hw->x) - abs(oldX));
+		int dY = abs(abs(hw->y) - abs(oldY));
+		double threshold = 90.0;
+
+		/*
+		xf86Msg(X_INFO, "\nx=%d, y=%d, millis=%d, oldmillis=%d,
+				realoldmillis=%d, Ax=%d Ay=%d dx=%f dy=%f dtime=%d\n",
+				hw->x, hw->y, hw->millis, oldMillis, oldTimeMillis, dX,
+				dY, dx, dy, elapsed_time);
+		*/
+		/* Ignore deltas as they couldn't possibly happen in so little time */
+		if (elapsed_time <= 20 && (abs(dx) >= threshold || abs(dy) >= threshold)) {
+			dx = 0.0;
+			dy = 0.0;
+			wasTimeSkipped = FALSE;
+		}
+		/* A comparison between the timestamp in priv->move_hist and hw->millis shows
+		 * that something went wrong and that an event was skipped, hence these
+		 * deltas are wrong.
+		 * Let's ignore the deltas and set wasTimeSkipped to TRUE as the next deltas
+		 * will be wrong too.
+		 */
+		else if (oldTimeMillis > 0 && (oldMillis != oldTimeMillis)) {
+			dx = 0.0;
+			dy = 0.0;
+			wasTimeSkipped = TRUE;
+		}
+		/* Something went wrong and an event was previously skipped, hence these deltas
+		 * are wrong. 
+		 * Let's ignore the deltas and set wasTimeSkipped to FALSE as the next deltas
+		 * should be good.
+		 */
+		else {
+			if (wasTimeSkipped) {
+			dx = 0.0;
+			dy = 0.0;			
+			}
+			wasTimeSkipped = FALSE;
+		}
+		oldTimeMillis = hw->millis;
+
+	}
+
     *dxP = dx;
     *dyP = dy;