Error "Cannot find cached 0sugar-launch implementation."

[her cex]

When I run Gcompris collection activities, I get this error Error "Cannot find cached 0sugar-launch implement". At first everything was ok then, after launching ( or installing ) many activities, almost all of them, I got this error.
And also I could not run etoys, scratch and tamtam on USR, do you have any solutions ?

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net.gcompris.hanoiRealActivity-1.log

Exited with status 0, pid 2411 data (None, <open file '<fdopen>', mode 'w' at 0xa4764f0>, 'e804cd8418cb0594c6494dd8d219f8edb59f90dd')

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net.gcompris.enumeratActivity-1.log

Exited with status 0, pid 1715 data (None, <open file '<fdopen>', mode 'w' at 0xa476498>, '0ea9a46059ff9380ca3c142da3d6d10ff1bab9d9')