'make' is failing due to _iconv_close symbol missing

I am building from source on Mac OS 10.5.  I have successfully built Apache 
and MySQL, but PHP is giving me difficulties.

Configuration goes without any problems:

../configure --prefix=/usr/local/php --with-mysql=/usr/local/mysql --with-apxs2=/usr/local/apache/bin/apxs 
 --with-zlib=/usr --with-iconv-dir=/usr

But when I do a make I get the following error (sorry it's a big line):

Undefined symbols:
  "_iconv_close", referenced from:
      _php_iconv_string in iconv.o
      _php_iconv_string in iconv.o
      __php_iconv_strlen in iconv.o
      __php_iconv_strpos in iconv.o
      __php_iconv_mime_decode in iconv.o
      __php_iconv_mime_decode in iconv.o
      __php_iconv_mime_decode in iconv.o
      _zif_iconv_substr in iconv.o
      _zif_iconv_substr in iconv.o
      _php_iconv_stream_filter_dtor in iconv.o
      _zif_iconv_mime_encode in iconv.o
      _zif_iconv_mime_encode in iconv.o
  "_iconv_open", referenced from:
      _php_iconv_string in iconv.o
      __php_iconv_strlen in iconv.o
      __php_iconv_strpos in iconv.o
      __php_iconv_mime_decode in iconv.o
      __php_iconv_mime_decode in iconv.o
      _zif_iconv_substr in iconv.o
      _zif_iconv_substr in iconv.o
      _zif_iconv_mime_encode in iconv.o
      _zif_iconv_mime_encode in iconv.o
      _php_iconv_stream_filter_factory_create in iconv.o
ld: symbol(s) not found
collect2: ld returned 1 exit status
make: *** [libs/libphp5.bundle] Error 1

I have checked that the libiconv library is present in /usr/lib.  I have 
even tried building the latest libiconv.  Neither of these have resulted in 
getting past this error.

I'm not sure how to proceed.

Dale Hopkins