I've been asked to create some ads to go on a site that
specifies "Advertising requiring the use of plug-ins like Flash and
Shockwave must utilize "sniffer" code to detect if the user has the
required plug-in and display an alternate image if the user does
not have it. ".
How do I do this? Are they expecting me to supply the
expected the host site to have a site-wide function to handle that.
What is the normal way of doing this?