Some folks are occassionally hitting a problem where they receive an error similar to the following when they try to run autoconf on the serval-dna repository (or indeed other software):
autoconf AC_PROG_JAVAC possibly undefined macro
This is extremely annoying, and doesn't really give any clues as to the cause. A bit of googling reveals that this can be fixed in most cases by running:
autoreconf -i
Then autoconf should be able to be run without further problems.