Search requests should ignore accents (C++ API)?

Hi,

I am using libxapian in a C++ project (hence I am using Xapian's C++ API)
and some user has requested that search requests should ignore accents.
E.g. when the user searches for "Herr Müller" he expects that "Herr Muller"
is also a search hit.

Is this possible in Xapian?
Do you have any links to the documentation of that feature?

Thanks for your help,
Kim