[Typo3] Different alttext in GMENU

[Tim Riemenschneider]

Hi!

is it possible to have a different alt-text in a GMENU?

I have a GMENU like this:
temp.menu.2 = GMENU
temp.menu.2.NO {
   # wrap
   wrap = |<br />

   XY = [4.w], [4.h]+2
   backColor = #006822

   4 = IMAGE
   4.file = fileadmin/template/Bilder/Button2_norm.gif
   10 = TEXT
   10.text.field = nav_title // title
   10.offset = 10,9
   10.fontSize= 10
   10.fontColor = black
}

This uses the field "nav_title" (when set) as Menu-Title.
The alt-text is set to the same text, but I want it to be always 
"title", even when "nav_title" is set.
Is that possible? (How?)

cu
   Tim