Thanks farshizzo! After trying some things I managed to get the reflection the way I wanted. Putting the light on the position of the mirror seemed to do the trick. Because I have several conditions (where participants view the world through the eyes of the avatar or through a point outside of the body of the avatar) I had to disable the headlight and add a light that pointed on the avatar, which had to be the same as the light on the mirror. Anyway, the problem is solved
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