CSS with IE - is the -ms-filter required or not?
I have been learning about IE's rather ridiculous-looking requirements for shadows, gradients, etc., and I'm running into some contradictions on this point:

Many sites suggest the following lines are necessary for a gradient/shadow combination:

    filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='#FFFFFF', EndColorStr='#F8F8F8') progid:DXImageTransform.Microsoft.Shadow(Strength=2, Direction=170, Color='#C6C6C6');
	-ms-filter: "progid:DXImageTransform.Microsoft.gradient(startColorStr='#FFFFFF', EndColorStr='#F8F8F8') progid:DXImageTransform.Microsoft.Shadow(Strength=2, Direction=170, Color='#C6C6C6')"; }

<a href="www.css3please.com">CSS3Please.com</a> suggests only the first filter is necessary for full compliance with IE 5.5-9, i.e. that the -ms-filter is of no use at all. Is -ms-filter needed any more or was that a temporary case in IE's development?
CSS with IE - is the -ms-filter required or not?
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I have been learning about IE's rather ridiculous-looking requirements for shadows, gradients, etc., and I'm running into some contradictions on this point:

Many sites suggest the following lines are necessary for a gradient/shadow combination:

    filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='#FFFFFF', EndColorStr='#F8F8F8') progid:DXImageTransform.Microsoft.Shadow(Strength=2, Direction=170, Color='#C6C6C6');
	-ms-filter: "progid:DXImageTransform.Microsoft.gradient(startColorStr='#FFFFFF', EndColorStr='#F8F8F8') progid:DXImageTransform.Microsoft.Shadow(Strength=2, Direction=170, Color='#C6C6C6')"; }

<a href="www.css3please.com">CSS3Please.com</a> suggests only the first filter is necessary for full compliance with IE 5.5-9, i.e. that the -ms-filter is of no use at all. Is -ms-filter needed any more or was that a temporary case in IE's development?