gdImageCreateFromGif and gdImageColorExact

If I call gdImageCreateFromGif to open a GIF89a file (as written earlier
with GD), should I be able to call gdImageColorExact to get access to a
color in the color map? Seems that if I do so, gdImageColorExact returns
-1, even though the requested RGB exist in the file's color map. If I
use gdImageColorAllocate the color is defined again in the color map,
resulting in an additional entry for that color. I need to avoid this.

Am I missing something?
-- 
Roger Oberholtzer

OPQ Systems / Ramböll RST

Ramböll Sverige AB
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