make ctags broke with

Making ctags in po
make[1]: Entering directory '.../mutt/po'
make[1]: *** No rule to make target 'ctags'.  Stop.
make[1]: Leaving directory '.../mutt/po'
Makefile:867: recipe for target 'ctags-recursive' failed
make: *** [ctags-recursive] Error 1

and once fixed the same in intl/

Note that this ctags target scatters tags files over directories.
If you use exuberant ctags then simply run
ctags -R
once in mutt's root dir instead.