I have used the following pre-deletion confirmation code on my sites for ages.

Code:
<input type="button" class="btn" value="Clear Order" onclick="if (confirm('Delete Order?')) {location.href='somepage.php';}"/>
Just recently it appears that some IE8 browsers are essentially ignoring the conditional check and charging on to the target link rergardless!

There seems to be considerable chatter on the forums about IE8 javascript handling but nothing definitive on this common piece of code.

Any clues?