Javascript treats '0' different to 0. '0' is a string, and doesn't seem to

Javascript treats '0' different to 0. '0' is a string, and doesn't seem to
match a boolean comparison.  Or at least you get some odd results.  I have
fancy highlighting off, and '0' makes it appear.  Also removed some odd
javascript:

  this.checked = !(this.checked)

on every message check box, what was this for?  Firefox makes that a stupid
bit of code, as you click on a check box, and it unchecks it immedately
making it impossible to select messages :)

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