*hesistates*

I'm not quite sure I understand what you're trying to do, but I don't see there being a problem in trying to nest both of them?

Code:
On *:TEXT:*:?: {
  if ($away) { commands for away system }
  else {
    volume_script
  }
}

If necessary, you can also always include additional if-statements into the if ($away) section.

Dana