Apache setup question

["Chuck Wannall" <cwannall@xxxxxxxxxxx>]

I want to make my Apache server unavailable for a short period each day
while save files are being created.

I would like to have the system display a brief 'system unavailable - try
again soon' message page.

I want to be able to turn this on and off at the appropriate times.  If
necessary, I could accept hard coding a time range into the config file.  

This needs to work on all input to the server, regardless of page type
(fixed, cgi).

I do not want to have to start/stop the web server if at all possible.

Any suggestions on where to look or what to change?

Thanks in advance,

Chuck Wannall
California Institute of the Arts