Logging clickthrough event

[grommie]

I am trying to find a way to generate a message to an external server
from the browser on a click event. The click needs to send the
message and then do an HTTP get of a linked page. These are two
separate actions.

The page that is being linked to is not under my control, so I cannot
do it there.

I have tried to tried to insert functions at onUnload, but the
function loads the next page before I can execute an iForm to cause a
message to be sent from the client.

Any thoughts?