My experience - No Problem.

My situation is quite similar as yours,
- I filed I-485 with my wife (Sept. 2003) based on an approved I-140 (NIW) while I was a student.
- Before I-485, I filed OPT application in August 2003, received OPT in Oct. 2003.

So, I had no problem in getting OPT. This is just for your information. You case may vary.