Solved! Thanks Bryan you were right! I was using matlab symbolic function that doesn't support te setmaple command. I launched matlab-sym-maple.bat from the bin directori of matlab and now all works.. thank you all

i have installed the 11.01 version, then i've also tried to update it at 11.02 with the upgrade on maple site. About the version: Maple Toolbox for MATLAB: 322622 i've no matlab's version of the toolbox but only installed maple toolbox for matlab... so i didn't understand your last request...