changing the REFER on a link
 

is it possible to force a refer via php or cgi?

example:

i have lots of traffic from lots of domains & sources coming into one url. that url is a php script which redirects the traffic based on where i wanna send it, country ip, etc. however, it passes along the original refering url. id like to be able to force the refer to show the php page, not the previous url that someone clicked on or whatever.

suggestions?