oil coming out of exhaust

I have a 98 sebring jxi, i was wondering if anyone could help me?? When i was siiting at a red light I seen some smoke coming from my exhaust, its kinda has a blue tint to it, and when i start to accelerate smoke comes out of the exhaust but then it quits. Everytime i check my car oil, about every 2 weeks its about maybe a 1/2 or 1 quart low. Could anyone tell me what the problem could be, or what i need to do to fix it.

Thanxs,
Gary Teague