[Typo3] tt_news and last item of each category

[Pierre Rouwens]

Hi all,

I m in trouble with configuring the tt_news i need to display only the 
last one item of each category, i ve tried as explained int the tt_jnews 
manual like this :
rsp.news < plugin.tt_news
rsp.news {
    code >
    code = LATEST
    catImageMode = 0
    catTextMode = 1
    listOrderBy = title asc
    listGroupBy = category
}
but it doesn't work here...
where did i mess somthing ??
PS : TYPO3 3.8 and tt_news v2.2.21

Thanks in advance for any clues

Pierre