I would normally agree with you, but the term "hack" in css already has a relatively well defined meaning as "goofy piece of CSS to work around a browser bug"[1]. While I do think it's appropriate to isolate such things so you can remove them when you stop supporting a browser, I don't think they'd belong in a shame.css file. Then again, maybe that's just getting too fetishistic about organizing code.

[1] http://www.quirksmode.org/css/csshacks.html