It's easier to just run a test than digging through the server to find out if .htaccess/mod_rewrite is available.
To keep from having a site-wide impact:
1.) Create a test directory on your old site/server, say /123-testing/
2.) Put an .htaccess file in the /123-testing/ directory with the following:
RewriteRule .? http://www.webmasterworld.com/apache/ [R=301,L]
3.) Type your-old-site.com/123-testing/anything.ext into your browser.
If you end up back here let us know it worked. If not, then you'll need to find the config file and make the necessary adjustments.