I've not seen that exact error, but a whole bunch of errors much like it. I think it is a bug (or a series of related bugs) in the paragraph composer. Most of the time, I see it when I'm using the World-Ready Composer when I should be using the Paragraph Composer, or the Single-Line Composer. Doesn't mean that it's not a bug, but a switch in composers will at least let you get your document out the door without deactivating hyphenation. If you're not familiar with switching composers, you can find it in the Justification menu (control-alt-shift-J on Windows, and something really similar on OS X that I can't recall). Does that change anything for you?
Ooooh, it worked!!! You were true, there was an override on my paragraph and it was on word-ready composer instead of paragraph composer. I removed the override and it solved the problem. Thank you so much!