Trying to use "wlist" to create Page with tag listings

I am trying to create a page with an automatic listing of posts with certain tags.
I have done this before on different wp blogs and it worked fine before, but its not working on my current site and I can’t figure out what I’m doing wrong.
I’m using the
[wlist request= “tag=tagname”]
function, but its not working.
On the page, it just appears exactly like that. Is there some setting I need to enable or plugin I need to get?
Thanks a lot