[Dev-C++] how to write configure.ac with shared_ptr.

Hello,

I'm struggling with configure.ac with shared_ptr checking.
I want to check if there is either tr1/boost_shared_ptr.h or
boost/shared_ptr.hpp but I have no idea how to do it with autoconf.

I just added AC_CHECK_HEADER like below,

AC_CHECK_HEADER(tr1/memory)
AC_CHECK_HEADER(boost/shared_ptr.hpp)

but ./configure says
...
checking tr1/memory usability... no
checking tr1/memory presence... no
checking for tr1/memory... no
checking boost/shared_ptr.hpp usability... no
checking boost/shared_ptr.hpp presence... no
checking for boost/shared_ptr.hpp... no
...

even though they both exist actually.
Does anyone know about what to do ?

Thanks,

Hiroyuki Yamada