This is what automake told me to do:
$ ./autogen.sh
...
automake: warnings are treated as errors
/usr/share/automake-1.12/am/ltlibrary.am: warning: 'libcomedi.la': linking libtool libraries using a non-POSIX
/usr/share/automake-1.12/am/ltlibrary.am: archiver requires 'AM_PROG_AR' in 'configure.ac'
lib/Makefile.am:2: while processing Libtool library 'libcomedi.la'
...
autoreconf-2.69: automake failed with exit status: 1
AM_PROG_AR is new in automake-1.11.2. For further details, see:
http://lists.gnu.org/archive/html/bug-automake/2012-05/msg00009.html
AM_MAINTAINER_MODE
+AM_PROG_AR
AC_PROG_CC
AM_PROG_CC_C_O
AC_PROG_CC_STDC