Turn The InnerHTML Of A Div Into A Number?

I'm using parseInt to try to turn the innerHTML of a div into a number. Pretty straight-forward and it works for every one except the string 08 and 09. works for 01-07, works for 10 and higher, just not 08 and 09. This is in Chrome and Firefox. In IE it works. Here's some code to illustrate the issue.

var items = ['04', '05', '06', '07', '08', '09', '10', '11'];
for(var i in items){
document.write(parseInt(items[i]) + '<br>');
}

where you should see 8 and 9 it just comes back as 0 (except in IE 9).