[TYPO3] gmenu alttext for images

[Mario Sargac]

Hi to all,

Is there a way to change the default (title) alttext for GMENU? I tried 
using:

imgParams = alt={$someVar}, which 'works' - but then the problem is I 
don't know how to define separate values for each menu item (I have 5 of 
them)

imgParams = alt={page:subtitle}, which unfortunately doesn't work in my 
case, but would be the best solution, as I'd like to have a subtitle for 
the alt atribute of the gmenu images...

Anyone with a helpful hint, maybe?

Thank you & all the best,
Mario