XmlDataProvider XPath

Hi,

my XmlDataProvider works on an xml file like this:

<config_cps><func_list><func id="A27328"><BLOCKS max_count="1" write_id="46" read_req_id="44" read_rep_id="45" session_id="6"><BLOCK id="1" frame="10" framelen="32"><ITEMS max_count="20"><ITEM id="1" type="STRING" size="16" value="111"/>
            ....</ITEMS></BLOCK></BLOCKS></func><func id="A29086"><BLOCKS max_count="2" write_id="49" read_req_id="47" read_rep_id="48" session_id="7"><BLOCK id="1" frame="1" framelen="61"><ITEMS max_count="14"><ITEM id="1" type="CHAR" size="1" value="222"/>
            ...</ITEMS></BLOCK><BLOCK id="2" frame="10" framelen="32"><ITEMS max_count="20"><ITEM id="1" type="STRING" size="16" value="333"/>
            ....</ITEMS></BLOCK></BLOCKS></func><func id="A29874">
    ....</func></func_list></config_cps>

I set the XmlDataProvider.XPath = "config_cps/func_list/func[@id='" + AppId + "']/BLOCKS"
and in the XAML I bind my controls like:

<TextBox DataContext="{StaticResource dataProvider}"
         Text="{Binding XPath='//BLOCKS/BLOCK[@id=1]/ITEMS/ITEM[@id=4]/@value',
                Converter={StaticResource StrConverter}}"/>

But it seems to not "filter" on the func node. So my doubt is: the XPath I set into XAML, overwrites the one I set in code or it works over a "query" deriving from it?

Daniele.