Hi,
I'm only vaguely familiar with the spell checker internals, but AFAIK, OOo itself is rather agnostic about the exact algorithm used to come up withsimilar words - that's an implementation detail of the checker engineused. For OOo, that would be aspell, for SO, one out of several commercialproducts.
Has someone nicely contributed an interface to aspell? If not, then the spellechecker being used in Myspell 3 based and again the "bug" is not a spellchecker bug but instead a dictionary bug since MySpell let's the dictionary author speciify which letters to use in suggestions and even common substring replacement tables or letter swaps.
Kevin