I'm trying to build libmemcached with SASL support on OS X Mountain Lion.

I have built memcached (1.4.15) with SASL support:

    $ memcached -S -vv
    Initialized SASL.
    slab class   1: chunk size        96 perslab   10922
    ...
    slab class  42: chunk size   1048576 perslab       1
    <17 server listening (binary)
    <18 server listening (binary)
    <19 send buffer was 9216, now 3728270
    <20 send buffer was 9216, now 3728270
    <19 server listening (udp)
    <20 server listening (udp)
    ...

I am trying to build libmemcached with SASL support too. I have tried the following:

    $ ./configure --prefix=/usr/local \
      --with-memcached-sasl=/usr/local/bin/memcached
    ...
    $ ./configure --prefix=/usr/local \
      --with-memcached-sasl="/usr/local/bin/memcached -S"
    ...

But the resulting configuration summary is the same for both:

Configuration summary for libmemcached version 1.0.11
       * Installation prefix:       /usr/local
       * System type:               apple-darwin12.2.0
       * Host CPU:                  x86_64
       * C Compiler:                i686-apple-darwin11-llvm-gcc-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.11.00)
       * C Flags:                    -O2 -Werror -Wall -Wextra -std=c99 -Wbad-function-cast -Wmissing-prototypes -Wnested-externs -Woverride-init
       * C++ Compiler:              i686-apple-darwin11-llvm-g++-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.11.00)
       * C++ Flags:                  -O2 -Werror -Wall -Wextra -Wpragmas -D_FORTIFY_SOURCE=2 -Waddress -Wchar-subscripts -Wcomment -Wctor-dtor-privacy -Wfloat-equal -Wformat=2 -Wmissing-field-initializers -Wmissing-noreturn -Wnon-virtual-dtor -Wnormalized=id -Woverloaded-virtual -Wpointer-arith -Wredundant-decls -Wshadow -Wshorten-64-to-32 -Wsign-compare -Wstrict-overflow=1 -Wswitch-enum -Wundef -Wunused-variable -Wwrite-strings -fwrapv -ggdb
       * CPP Flags:                 -I/usr/local/include
       * Assertions enabled:        no
       * Debug enabled:             no
       * Warnings as failure:       no
       * SASL support:              

Am I doing something incorrectly? Thanks.