Routing issue - again!

[eluser]jdav3579[/eluser]
I am fairly new to code igniter and cant seem to get my head around the uri routing thing. I have read numerous threads here but still can't seem to apply it to my own problem.

I think it should be straight forward to do, but just dont get it.
I have the following routing:
$route['page/index/CONTACT-US/:any'] = "page/contact";
so if the url is blah/page/index/CONTACT-US everything gets sent to this page/contact

but I also want to be be able to pass in parameters.
The contact function its like this

function contact($msg=null){}

I just want to pass the paramters into the function so for example:
blah/page/index/CONTACT-US/thanks

then the function would get "thanks" in the msg variable.

Any help kindly appreciated!!