[TYPO3-dev] GIFBUILDER TEXT height - strange behaviour of +calc

[Jonas Schnaitmann]

Hi,

i have the following Typoscript to generate an image with a vertical 
text in it:

temp.corner_right = IMG_RESOURCE
temp.corner_right.file = GIFBUILDER
temp.corner_right.file {
    XY = 58, [20.h]+141
    backColor = #ffffff
   
    5 = IMAGE
    5.file = fileadmin/templates/img/bg_main_right_text.gif
   
    20 = TEXT
    20.text = aa
    20.fontFile = fileadmin/fonts/verdanab.ttf
    20.offset = 53, [20.h]+136
    20.angle = 90
    20.fontColor = #7b7b7b
    20.fontSize = 12
}

The problem is that the height of the TEXT isn't calculated correctly 
sometimes, depending of the text value.
If I set "da" as a value for 20.text, the "right" (= upper) side of the 
text has a bigger offset to the background image (5.file) as if I set 
e.g. "aa" as a value.
It seems that [20.h]+136 returns wrong values for some characters.

Does anyone know if I made a mistake or is that a problem of the GIFBUILDER?

Thanks, Jonas