If you have proper midi equipment (soundcard + software), that is, if other midi files are played on your computer, you just need a midi plugin.
I think that from
]]http://download.liveupdate.com/plugins/c51n9x.exe[/url]
you can get the free crescendo plugin for netscape. When installing, it asks you for the directory where to install. Whatever is offered, choose your K-Meleon/plugins folder (usually in C:\Program Files\) - so what you should type for the plugin location will probably be as follows:
C:\Program Files\K-Meleon\Plugins\
(if you have K-Meleon in another folder, that is not applicable).
After installation, restart K-Meleon. The plugins folder, btw should contain the file npmidi32.dll.
If it doesn't work, there may be something wrong with your soundcard's midi settings. There are probably also other midi plugins. If I remember correctly, QuickTime can also handle midi (not sure, though). Anyway, you can post here about it then.