Sarah,
Note that Tim asked for International standards, while ANSI is purely a US
focused standards group.

The unfortunate and quick answer to Tim's question is no, there is no
international standard available to work from. Today the best approach might be
to review the top consumer IVR apps in each target country to determine how they
are managing the interface. Telcos, banking and transportation usually are good
industries to find these high usage apps.

I suppose that Ms. Gardner-Bonneau's work is a step in the right direction, but
perhaps she might consider thinking outside of the US/N America to adapt these
best practices to a global perspective.

One of the most frequent faux paus I see from US based IVR developers is the
reliance on the alpha portion of the phone keypad. Many countries lack any
alpha characters on the keypad, and even those mobile devices that carry them,
don't usually match to the US alpha/numeric scheme.