mod-rewrite help please

[lcp03o]

I am trying to rewtire this url

http://www.computing-forums.com/vie...php?p=5746#5746 to
www.computing-forums.com/5746#5746.html

I am using the following rule, but it is not working. Where am I going wrong??

RewriteRule ^{([0-9]+)-([0-9]+).html$} viewtopic.php?p=$1 [L]

Thanks