Spaces and Dashes Headache

[refiking]

I'm sure this is a simple one, but here's the issue I'm having.  If I type the url with the spaces, the page is shown, but if I type it with dashes instead, it isn't shown.  Now, I wrote a little snippet of code to replace the dashes with spaces and when I went to the direct link, it worked perfectly.  When I tried the static version through mod rewrite, I got the 404 error.

 

Here is the little snippet of code I put in my file that works on the dynamic link:

$newid = str_replace("-", " ", $id);

 

and here is the rewriterule:

rewriterule ^articles/([^-]+)\.html$ refitester.php?id=$1 [L]