After investigating Chromium bug 6733 (http://code.google.com/p/chromium/issues/detail?id=6733) I came to the conclusion that the fix for rdar://problem/6489314 did not go far enough. Change 39882 does correct the parsing of NaN, but left the parsing of infinite values broken when compared to Firefox, IE and Safari 3.2.1.
<rdar://problem/6514842>
Created attachment 26938 [details] Fix
Fixed with revision 40133.