[BurningFrog]

The obvious solution is to have phone support days or hours.

If you only accept support calls at certain times, you can plan to do development at other times.

[cyberferret]

When dealing with local clients, that is certainly a possibility (and indeed was the case with me at one stage). But when you have customers all over the world, you have to basically be on call 24hours a day (also the case with me).

[majewsky]

Do you allow clients to shake you out of your sleep?