On OS X Leopard, the apache that comes installed is built as a
universal binary,
and it requires similar universal modules.  You can use "lipo" to
strip the httpd
binary down to your own architecture, but updates will probably
continue to
be universal, so you may be using lipo regularly.

An alternative approach is to build your mod_scgi.so file for the same
set of architectures.  Here's a Makefile that appears to accomplish
what's needed.  To use it for this purpose, use "make universal"
and "make universal_install".
----

APXS=apxs

# Extra args for building a multi-architecture version OS X 10.5.
UNIVERSAL="-arch ppc7400 -arch ppc64 -arch i386 -arch x86_64"

all:
         $(APXS) -c mod_scgi.c

install:
         $(APXS) -i -c mod_scgi.c

universal:
         $(APXS) -c -Wl,$(UNIVERSAL) -Wc,$(UNIVERSAL) mod_scgi.c

install_universal:
         $(APXS) -c -Wl,$(UNIVERSAL) -Wc,$(UNIVERSAL) mod_scgi.c

clean:
         rm -rf mod_scgi.o mod_scgi.lo mod_scgi.slo mod_scgi.la .libs