Soft body problem in game engine with keyboard sensore

Hi, I am beginner in blender and its game engine. I am trying to simulate a rope using soft bodies and hit that rope with a rigid object. The rigid object starts moving toward the rope when a keyboar key is hit. A keyboard sensor is created using game logic and it is atteched to the rigid object. The problem is when the game starts and I press the designated key, the rigid object moves and collides with the rope as a static rope not as soft body rope!!! If I chenge the sensor type to always instead of keyboard, things work fine and the rope react as a soft body rope as expected. I tried a lot of things and spent hours trying to make it works with no luck, is this a bug in blender game engine?

I attached my .blend file if you can help me figure out what I am doing wrong?

looking forward for your help

Attachments

test_soft.blend (720 KB)