MapActivity Gesture Problem

I use a MapActivity and have the following problem:

When I zo开发者_开发技巧omin or zoomout with a multitouch-gesture, sometimes the Map freezes and a blank display is shown. Has anybody seen this?

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Have posted some code here which works for me. Random MapView Force Close : NullPointerException com.google.googlenav.map.Tile.getTile

I think this happens when you zoom in too much and the MapView does not find the tiles.