odd brake light problem...

[entrapm3nt]

Ok so all my lights work but when i press on the brake the driver side brake light goes out. along with the running light on the driver side. when i let go of the brakes. the lights work. I checked the brake pedal switch and there is indeed a hole where the sensor goes. However, the lights are not staying on when the car is off. it seems to be working correctly. and i dont think its the bulb because the bulb works when i let off the brake pedal. also, if it was the brake light switch wouldnt it effect both lights? i searched a lot and can find no one with a similar problem. the car is a 93 vert. any ideas? thanks in advance...