I'm experiencing the same problem - the "DOMParser is unidentified" message appears twice on every page in the website. Occurs on every computer in my house.
The problem happens only in Internet Explorer - Google Chrome runs fine. The problem does not happen on any website other than Sprint.
Running IE 8 under Windows XP.
I'll try the cache and cookies clearing idea, but it's odd that every one of my computers is doing this.
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