[flexcoders] Water Mark on Application like "Flex Charting Trial"

[hworke]

  Hello,

  I am distributing a trial version of my
  flex application. On my trial version of
  the application I want to put a water mark
  on the middle of the application which
  will indicate that it is a trial version.
  As an example- Flex charting trial version
  also has water mark on the middle of every
  chart.

  How do I put my own water mark on my
  application?

  Regards