Unable to regenerate libstdc++-v3 configure

[Aaron W. LaFramboise]

When I try to regenerate configure, using autoconf 2.59, I get:

configure.ac:187: error: possibly undefined macro: AC_DEFINE
       If this token and others are legitimate, please use m4_pattern_allow.
       See the Autoconf documentation.

If I run autoconf again, it works without complaining, but then the 
resulting configure script doesn't work:

configure: CPU config directory is cpu/i386 

configure: OS config directory is os/mingw32 

/mingw/src/svn/libstdc++-v3/configure: line 4096: syntax error near 
unexpected token `fi' 

/mingw/src/svn/libstdc++-v3/configure: line 4096: `fi' 

make[1]: *** [configure-target-libstdc++-v3] Error 1 


What is going on here?