Brake light not working right

[nova_gh]

I've noticed this on a couple other grand ams including my 99 SE.

When you press the brake and the brake lights illuminate, only half of the lense lights up. In other words, there are two brake light bulbs in each driver and passenger side lense, but only one of the bulbs lights up in each lense. I've replaced the bulbs and they still don't work. Kind like this....

------------\
ok X \
\
ok ok ok \
---------------\

thats the driver side tail light, all five bulbs are good, but one w/ X doesn't work. But the X bulb is also tail light bulb so when my head lights are on its on too, it just doesn't illuminate when the brake is applied. The other tail light has this problem too. I was wondering if anyone else found a loose connection or broken wire somewhere?

I'll try and post a pic later....