ISBNs

The help section for the “Other Works” area on IMDb says that if you're adding a book, you must provide the ISBN-10, because ISBN-13 is not supported. It even suggests going to Amazon to find the ISBN-10. However, this advice is outdated. Books published today do not have an ISBN-10, because all valid ISBN-10 numbers have already been used. That’s why the publishing industry moved entirely to ISBN-13. In fact, new ISBN-13s now begin with 279 because they ran out of 278s. ISBN-13s starting with 279 cannot be converted to ISBN-10 — there's no backwards compatibility. So what am I supposed to do if I only have an ISBN-13 that can’t be converted? (I can’t be the first person encountering this issue, and it makes it impossible to add new books to IMDb under the current rules).