Removing column header separator lines (flex)

This took me a while to figure out so I thought I would post it on here just in case someone else is having the same problem.

I have an Advanced Data Grid, but I don't want any separator lines between the headers. There are 2 styles and 1 property you need to set in an AdvancedDataGrid to make this happen.



The styles are:
header-separator-skin
header-sort-separator-skin

The property is:
sortExpertMode

I figured setting the styles to "null" would work, but it doesn't.

Here is what you need to do:

headerSortSeparatorSkin="mx.skins.ProgrammaticSkin"
headerSeparatorSkin="mx.skins.ProgrammaticSkin"
sortExpertMode="true"

Or if you'd rather set the styles in CSS:

header-separator-skin: ClassReference("mx.skins.ProgrammaticSkin");
header-sort-separator-skin: ClassReference("mx.skins.ProgrammaticSkin");

Sample with source

Thanks to http://theflexguy.com/index.php?option=com_idoblog&task=viewpost&id=104&Itemid=54 for your post on this!