Revellers play in the mud during the 15th Woodstock Festival in Kostrzyn-upon-Odra River, close to the Polish and German border, August 1, 2009.[Xinhua/Reuters]
![Revellers play in the mud during the 15th Woodstock Festival in Kostrzyn-upon-Odra River, close to the Polish and German border, August 1, 2009.[Xinhua/Reuters]](http://images.china.cn/attachement/jpg/site1007/20090803/000bcdb95f1d0be08e9f34.jpg "Revellers play in the mud during the 15th Woodstock Festival in Kostrzyn-upon-Odra River, close to the Polish and German border, August 1, 2009.[Xinhua/Reuters]")