Can I override the default DNS settings on an HTC Evo without root access? Is there any way to override the Sprint DNS server(s) used by default on the 3G connection of an HTC Evo running Froyo without root access?

The reason I want to do this is because some sites are able to resolve when I'm using OpenDNS or Google DNS while connected via WiFi at home, but when I'm on 3G, the same sites come up as page not found, so the easiest culprit to blame is DNS.
Everything I've seen suggests you can only do it if your phone is rooted.  Here's a tutorial for those with rooted phones.