[OS X Emacs] native spellcheck?

[Michael Gilbert]

Hi —

Pardon a newbie's query... The "Features" page at the Aquamacs site reads "Spell-Checking. Aquamacs spell-checks your documents with the OS X spell-checker, supporting more than a hundred languages and system-wide user dictionaries." I just tested this with a word that was learned by the Mac OS dictionary (the name of the organization I work with). In TextEdit or Mail (native spellcheck aware apps), the word shows up unmarked. But in Aquamacs, (nightly build from a few days back), it shows up marked. How should I approach troubleshooting this?

TIA!

— Michael