I'm moving a working site to a new host, and I've got a puzzling problem with URL rewrite rules.

The new host is giving me 404's when I try to load a page that requires rewriting. It appears to be simply ignoring the rewrite rule.

For example, the URL http://www.mysite.com/list-Topics-OMH should be rewritten to http://www.mysite.com/list.php?Topics=OMH. On the old host, it is; on the new host, it isn't.

I've spoken to the new host's tech support about this. They've confirmed that the htaccess file is working in other respects (and I've since confirmed this myself). They say it must be a programming problem, not a system problem.

They speculated that it's due to some difference in the way the rewrite module works between the version of Apache on my development system (2.2.17) and their version (2.2.22). That seems unlikely to me, but I don't know what else to suspect.

Here's the contents of the htaccess file:

RewriteEngine on
Options FollowSymLinks
#RewriteBase is not needed because we are not rewriting the directory name.
#This rule transforms "list-t-key" to "list.php?t=key".
RewriteRule ^list-(.*)-(.*)$ list.php?$1=$2
Any suggestions? If it's something weird in htaccess, how can I find it? If not, how might I prove that and force them to look farther?