yet another FuzzyOcr version question

[polloxx]

I have another question concerning FozzyOcr 2.3b versus FuzzyOcr 3.5.1:
A spam picture like this: http://213.146.165.18/spam2.gif does generate
a SA FuzzyOcr score of 19 with version 2.3b (and gocr 0.40). With version 3.5.1
(and gocr 0.44)  does not generate a score at all. I'm sure the
systems works because
other picture spam messages are generating a score.
Both are running SA 3.1.7-2 on debian etch. How can I solve this?

P.