This is from an exchange on the OS X Server mailing list.

The OP was trying to get mcrypt compiled into his PHP5 install on a 64-bit machine running 10.5.4

On Jul 24, 2008, at 4:53 PM, Someone wrote:
> I’m trying to compile my own PHP (which I’ve done plenty of times
> in the past on other systems), but
> I need libmcrypt support. Because 10.5 OS X Server is all 64 bit, I
> need a 64bit php binary, which
> means all my linked libraries need to be 64 bit as well.
>
> I tried to compile libmcrypt by hand and with the SVN version of
> macports, but both versions give me
> the following error when I do `make test` after compiling php with
> them:
>
> dyld: Symbol not found: _arcfour_LTX__is_block_algorithm
> Referenced from: /usr/local/lib/libmcrypt.4.dylib
> Expected in: flat namespace
>
> Googling for this error just brings up a forum post on entropy.org,
> which isn’t much help. How can I get my 64bit php to play nice?
>
> I’m using CFLAGS=’-arch x86_64′ before all my ./configure
> statements to get a x86_64 build.
>

Jul 25 14:20:59 gerry org.apache.httpd[625]: httpd: Syntax error on line 1462 of /private/etc/apache2/httpd.conf: Syntax error on line 8 of /etc/apache2/sites/entropy-php.conf: Cannot load /usr/local/php5/libphp5.so into server: dlopen(/usr/local/php5/libphp5.so, 10): no suitable image found.
Did find:
/usr/local/php5/libphp5.so: no matching architecture in universal wrapper

—–

My response for solving the problem in a different way that I found on the Entropy.ch forums

—–

How about going the other way…..

I ran into a similar situation setting up an Intel Xserve with a new install of Leopard Server.
I was trying to get the entropy.ch PHP module (which contains mcrypt FYI) running and it would not load due to “no appropriate image found” errors.

Apache on Leopard is a fat binary and was trying to load as a 64-bit app, which of course means that all plug-ins, loadable libraries need to be 64-bit as well and the Entropy PHP doesn’t currently have a 64-bit x86 image.

Since this is for an Apache 2 web server and I would be using the pre-forked model and any single one of my requests that would be running PHP code would be very unlikely to need anywhere near more than even 1GB of RAM, I forced Apache to run as a 32-bit process so that the PHP module would load.

I did this by using the lipo command to thin out Apple’s apache2 binary (after making a backup of course) to just contain a 32-bit x86 image.

Here is a small shell script that will make a backup and run the lipo command:

#!/bin/sh -
#
#

cd /usr/sbin;
mv httpd httpd.ub;
lipo -info httpd.ub;
lipo -thin i386 httpd.ub -output httpd.i386;
lipo -info httpd.i386;
ln -s httpd.i386 httpd;