XML Parser Metadata - storing the attribute name of the translatable string

Hi 

I have an XML file which contains snippets similar to this:

<BUTTON id="btnPrevious" tip="Previous" url="nav_left_blue.gif"/>

<BUTTON id="save" label="Save"/>

I need to have the "tip" and "label" attributes translated so I have created the following data element entries in the XML parser:

BUTTON/attribute::label

BUTTON/attribute::tip

In both cases I have made the "id" attribute the ID to display, and I have ticked the "Append element name to ID"

In the string list window, the following values are are displayed in the ID column:

"btnPrevious.BUTTON"

"save.BUTTON"

The above is working perfectly

 

But, what I'd like to do, hopefully via parser metadata, is to store the attribute name in the properties of the source string, e.g. "tip" and "label".

I've tried several different XPaths and all I've managed to do so far is store the attribute value, e.g. "Previous" and "Save", which is not what I want.

I feel like I'm missing something really obvious here. Can anyone help with the correct way of doing this? 

Thanks

Mark