\macro dies if one of the arguments to the macro is "class"

eg.
\macro QTOPIA_ADD_APPLICATION(name,class)

The error message is not at all helpful:
/home/lramsay/depot/qtopia/4.2/src/libraries/qtopia/qtopiaapplication.cpp:4079:
Invalid syntax in '\macro'

Note that both CLASS and classname both work. Go figure.