I am familiar with this issue. I know, because I've implemented a working solution for my own web interface for openwrt (www.gargoyle-router.com). I solved it with a highly customized version of the mini-httpd-matrixssl noted above.
You can't solve this problem with the default version of mini-httpd-matrixssl. The default matrixssl implementation uses mutexes to make sure that it is thread safe. However, the version of uclibc used in Kamikaze 8.09 has a broken pthread implementation, and unless modified, matrixssl will die if you try to use it. On top of that, the default adapter functions for matrixssl die if you try to transfer over 16Kb. I had to fix these.
Also, the default authentication system in mini-httpd-matrixssl requires you have .htaccess files in EVERY directory where you have files -- it doesn't apply recursively. I had to patch this too.
Finally, the default version of mini-httpd-matrixssl only allows you to open up one port -- you can't have one port for http connections and another for https connections. This too has been patched.
If luci developers are interested they are more than welcome to shamelessly copy (all or portions of) my code -- it is GPL after all, and I make it freely available.