Thanks Bruno, This is a very welcome addition to Autoconf. As a matter of fact, some users had already suggested that we swallow your macros, and Paul had suggested that we wait until you feel it is mature enough.
It seems that this day has come! There remains mostly details to settle: the code will be tranformed for 2.54, which basically means that 2.13 compatibility stuff will be removed. Since you keep backward compatibility, this means we will have two sets of macros. For safety, it would be good that we have two different macro names. Also, it might introduce some additional work when changes are needed for one of the sets. Is that a problem for you?