Forgot to mention that I did try all the suggestions such as moving MH_BUNDLE_FLAGS in the Makefile and editing iconv.c using different iconv libs (MacPorts) -- nothing worked...

Bump... anyone? This is really screwing me as the version of PHP supplied by Apple won't run background CLI scripts and is missing some extensions I need to have

I finally resolved this by editing the Makefile as follows so that the first -L/usr/lib is changed to -L/opt/local/lib (I am using Macports)

MH_BUNDLE_FLAGS = -bundle -bundle_loader /usr/local/apache2/bin/httpd -L/opt/local/lib -laprutil-1 -lldap -llber -llber -lexpat -liconv -L/usr/lib -lpq -lsqlite3 -lldap -llber -llber -L/usr/lib -lapr-1 -lpthread 

Hope this helps someone else.

I confirm the same issue while compiling PHP 5.4RC2.
To reproduce it, you'll need to have MacPorts installed with iconv lib installed 
here. Basically, I already have a 5.3.8 built with MacPorts on my system.

Modifying the Makefile as rich06 suggested made it work, but shouldn't this be 
made by configure script ? I tried with --with-iconv-dir=/opt/local/lib, but it 
doesn't seem to work here

This issue should be solved, editing manually the Makefile isn't the way to go.

There seems to be linked with --with-apxs2 option.
Indeed, I first used --with-apxs2 (without value) and --with-iconv-dir=/opt/local 
(macports prefix). Here the compiler will take apxs system default (which is 
/usr/sbin/apxs), and for some reason also makes ignore --with-iconv-dir value.

If I use --with-apxs2=/opt/local/apache2/bin/apxs (apache2 macports prefix), then 
everything will be fine.

Closing.
Invalid usage of --with-apxs2 which expects a file argument:
--with-apxs2 --with-iconv-dir=/opt/local

I don't agree here, as ./configure --help says:

  --with-apxs2=FILE     Build shared Apache 2.0 Handler module. FILE is the 
optional
                          pathname to the Apache apxs tool apxs

So FILE is optional

This is a still an issue men and it's not related to --with-apxs2. This is my configure command line:

sudo ./configure --prefix=/usr/local --with-apxs2=/usr/sbin/apxs --with-ldap=/usr --with-kerberos=/usr --enable-cli --with-zlib-dir=/usr --enable-exif --enable-ftp --enable-mbstring --enable-mbregex --enable-sockets --with-iodbc=/usr --with-curl=/usr --with-config-file-path=/etc --sysconfdir=/private/etc --with-mysql-sock=/var/mysql/mysql.sock --with-mysql=mysqlnd --with-mysqli=mysqlnd --with-openssl=/usr --with-xmlrpc --with-xsl=/usr --without-pear --with-libxml-dir=/usr --with-iconv-dir=/opt/local --with-gd --with-jpeg-dir=/opt/local --with-png-dir=/opt/local --with-freetype-dir=/opt/local --with-mcrypt=/opt/local

As you can see, there is a file path for apsx2 option: --with-apxs2=/usr/sbin/apxs

But the make still fails. To make it work, I changed the Makefile, in particular the MH_BUNDLE_FLAGS, like suggested by rich06, as follow: -L/opt/local/lib

This is a bug, and it's still there. Reopen it, please.

If you are on OSX and using Xcode 4.3, make sure you install the command line 
tools. That should solve a good deal of extension compiling errors.

I had this same issue when compiling PHP5.4 on Mac OS X 10.6.8 ( Snow Leopard )

I tried both the local copy of the iconv library that and also tried to specify one that I got via fink.

I had to perform the correction that rich mentioned and changed the path to a the version of iconv that I compiled.

Same problem.  Makefile edit to point at /opt/local/lib worked for me as well.

This happens to me to compiling PHP 5.4.8 on MAC OSX 10.7 (Lion). Even with the 
Makefile edition fix proposed in the comments I still get the same error.

I have Macports and installed libiconv through macports. Tried a custom compiled 
libiconv to no avail.

see http://stackoverflow.com/questions/10457982/compiling-php-error-make-libs-libphp5-bundle-error-1
Makefile need to be modified under OS X. Or conflicts with libiconv version come out. I completely solved this problem on my MBP.