Netlibrary "hack"

So I'm working on my senior essay, and I need to look up a page number for a citation. I don't have the book with me, because I had previously used the online version from the Yale library database. While I'm waiting for a page to load, I notice the following line of code (I highlighted it with a red box - click for a larger version to pop up):


In case you can't read it, it says "HACK: Sometimes parent or parent.parent is inaccessible because we're trapped in somebody else's frameset."

Whaa...? Is this some poor programmer trapped in the Matrix? =P