[nickdangerME]

I don't have my rulebook on me, but I'll check tonight and see how I fared off the cuff.

It seems to me that if you are 100% sure of the serving error and know your partner is just not picking up on it, you should call it immediately after the serve, when the violation occurs. If you are only 99% certain, I can see waiting until after the point has been played to check with the scorekeeper to confirm the error, and then making your partner aware of the problem so the score can be corrected.

Even if you are 100% sure, I wouldn't have you do anything before the serve (other than try to discretely alert your partner to the potential problem). The serving team should have the responsibility of recognizing its own error. It has the opportunity to correct itself up to the time the serve is hit, and before that point there is no violation to call.

Finally, I would not wait for the table to notify me, unless I was sure that the scorekeeper knew what he or she was doing. My limited experience tells me that most high school scorekeepers (at least in this area) lack the experience and confidence to recognize the problem and promptly alert the umpire.

Nick