OT? how does the function reference work in katepart?

This may be off-topic, and if it is, I apologize.

KDE's Katepart offers syntax highlighting using the syntax .xml files.

The PHP syntax XML file (for example) has a very extensive function 
*list*, which highlights function names.  

Quanta also has pop-up tooltips that show what the arguments to a PHP 
function are. These don't show up in Kate, so I assume that they are 
specific to Quanta. Where are these defined?

are these the:
/usr/kde/3.5/share/apps/quanta/dtep/*/*.tag
files?  It looks like these may be the source of the tooltips, but these 
only seem to define return-types and PHP versions, not calling 
parameters.

I'm asking because I need to develop this same kind of support for the R 
statistical package.  Getting the list of R functions is easy, but I 
don't see how the function parameter reference works at all.

Any help would be appreciated.

Regards,

  - Brian