Firefox treeview.htc Cache???

Hi All,
I'm trying to create a treeview with the
Microsoft.Web.UI.WebControls.TreeView. It seems to work in both ie and
firefox but I wanted to remove postback events for the checkboxes in
the treeview. I read http://forums.asp.net/556179/ShowPost.aspx where
it says this can be done by modifying the treeview.htc. I did this and
it seems to work in ie.
When I tried in firefox it didn't make any difference so I made some
more changes to try to trigger a change. In the end I deleted the
treeview.htc file which removed all formatting and behaviour in ie
(which I expected), but in Firefox there is no change. It still
works!!!
I have only 1 treeview.htc file on the server so it couldn't be
confusing it with another, so I can only assume that it is being cached
or something.
Can anyone shed some light on this??
Any help would be much appreciated.
Cheers,
David.

David