The flower shape is more typical of Solanum linearifolium so I'm calling it that species; despite its name ('linear leaves') it can have divided leaves especially when young. The really diagnostic character to distinguish it from S. aviculare is fruit colour (orange-red to scarlet in S. aviculare; ochre-yellow and reddish purple at apex in S. linearfolium).
many thanks for id and hint. I hope it will develop fruits ... there were only 2 flowers in this young plant and I didn't notice any other in the surround.