> I am trying now to do a new build as i always do from 1.4.3.
> On this machine is the 1.4.3 release version.

Are you certain that all of user-land has been upgraded to 1.4.3,
or are you just in the process of doing so (from source)?  It
certainly looks like the latter.

> /usr/src/libexec/rmail/rmail.c: In function `main':
> /usr/src/libexec/rmail/rmail.c:193: warning: null format string

Please rebuild and reinstall the compiler before trying to
recompile the entire tree.

The compiler frontend has been modified to accept null format
strings as "valid", so that one can do format string checking of
the arguments passed to err(), warn() etc., and that's required
since several members of this family of functions can also be fed
a single NULL argument.

(I'll also point out that there is a fairly prominently placed
note in the 1.4.3 install notes that you need to do this when
doing a source based upgrade... ;-)

Best regards,

- H=E5vard