How should long messages be displayed

[Sébastien Hinderer]

Dear all,

One of my autoconf script has a long notice mesage, i.e. over 80
characters. I am already using m4_normalize to be able to write the
message nicely in the configure.ac file, but at the moment the printed
message generates a very long line and I am wondering whether something
is recommended to deal with this situation? Do I have to insert an
end-of-line character explicitly in the string, or is there a way to let
autoconf format the notice messages nicely by itself as is done for help
strings?

Many thanks in advance for any hint!

Sébastien.