How to exclude categories from layered navigation by xml?

[Tanito]

I found a suggestion how to do this in xml but as it does not work and I can only find ways to do it by changing core/local code, I'm posting here to see if anyone can shed some light on it.this is the suggestion I found:\[code\]<reference name="catalog.leftnav"> <action method="unsetChild"><alias>category_filter</alias></action></reference>\[/code\]I added this to the catalog_category_default and _layered handles but with no result. On checking the core code it seemed the correct name for the alias should be layer_filter_category and so I changed to that on both handles but that didn't work either.More as a desperation I also tried nesting reference in another reference to make sure it was loaded but I'm really unsure if this is correct at all?\[code\]<reference name="left"> <reference name="catalog.leftnav"> <action method="unsetChild"><alias>layer_filter_category</alias></action> </reference></reference>\[/code\]It would be much appreciated if anyone could let me know the correct way to do this by xml.Thanks a bunch in advance!