There's a case insensitive ext3 driver, but, frankly, running such a thing in production would scare me a bit, since you're rolling your own custom kernel with patched-in drivers. (Yeah, yeah-- we did that all the time "back in the day", but that was, like, 1997...)
There's a FUSE implementation, ciopfs, that implements case insensitivity as well. That would be a lot less scary to me to use in production than a patched kernel.
You could also use a case-insensitive filesystem, like VFAT, for the
/var/www folder hierarchy. I'd use a loopback mount in that case, such that you don't have to mess with your disk partitioning.