Words to be spell checked should be converted to NFKC first so that spell checking dictionaries don't need to hold all forms (NFD, NFC, mixed) of a word.

I'm going to sketch my thoughts on how to do it here in case I can't get back to the bug for a while. Anyone want to take it further?

In SpellChecker::GetSpellFailure in lingucomponent/source/spell/sspellimpl.cxx, rather than doing a poor man's hand created NFK into nWord, start with an nWord created something like:

icu::UnicodeString rIn(reinterpret_case<const UChar *>(rWord.getStr()), rWord.getLength());
icu::UnicodeString normal;
UErrorCode rCode;
icu::Normalizer(rIn, UNORM_NFKC, normal, rCode);
OUString nWord(U_SUCCESS(rCode) ? OUString(reinterpret_case<Sal_Unicode *>(normal.getBuffer()), normal.length()) : OUString());

then use nWord instead of rWord for the rest of the function.

Need to find a test for this.