Message during Backup

Hey All. I wanted to find out and see if there was a way of having WHM insert a page for sites while they are backing up. This serves many purposes but primarily as well a know for the backup to happen databases are locked. This makes dynamic softwares like forum communities throw many errors to their thousands of members while it is in progress. Other things happen like pingdom is triggered as well as other monitoring tools. Needless to say the ability to be able to force something to display while a site is backing up keeps many people calm. I know its possible on servers with out WHM as I've had it done before with a script. However now that we are using WHM, I wouldn't know how to go about it.