diff --git a/ocaml-camomile.spec b/ocaml-camomile.spec
index 968498f..64383ab 100644
--- a/ocaml-camomile.spec
+++ b/ocaml-camomile.spec
@@ -3,7 +3,7 @@
 
 Name:           ocaml-camomile
 Version:        0.8.3
-Release:        2%{?dist}
+Release:        4%{?dist}
 Summary:        Unicode library for OCaml
 
 Group:          Development/Libraries
@@ -14,7 +14,7 @@ License:        LGPLv2+
 URL:            http://sourceforge.net/projects/camomile/
 Source0:        http://downloads.sourceforge.net/camomile/camomile-%{version}.tar.bz2
 BuildRoot:      %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
-ExcludeArch:    ppc64 sparc64 s390 s390x
+ExcludeArch:    sparc64 s390 s390x
 
 BuildRequires:  ocaml, ocaml-findlib-devel, ocaml-ocamldoc, ocaml-camlp4-devel
 
@@ -60,6 +60,36 @@ applications that use %{name}.
 
 %patch1 -p1
 
+# This is a horrible hack to work around a bug in our ppc64 code
+# generator.  For some reason which we don't fully understand it barfs
+# on the long entry function created by the series of alias commands
+# at the end of public/charEncoding.ml:
+#
+#   let () = alias "IANA/csGB2312" "GB2312"
+#   let () = alias "IANA/GB2312" "GB2312"
+#   (* etc for 573 lines *)
+#
+# Use a sed script to change to the equivalent code:
+#
+#   let aliases = [
+#   "IANA/csGB2312", "GB2312";
+#   "IANA/GB2312", "GB2312";
+#   (* etc *)
+#   ] ;; List.iter (fun (a,b) -> alias a b) aliases
+#
+# The equivalent code contains just data plus a small entry function
+# so it doesn't break the ppc64 generator.  It's likely also to be
+# more efficient.  Since the code is equivalent, we do this
+# transformation on all arches, not just ppc64.
+#
+#   - RWMJ 2012-05-30
+
+mv public/charEncoding.ml public/charEncoding.ml.orig
+sed -e 's/let () = alias \("[^[:space:]]*"\) \("[^[:space:]]*"\)/\1, \2;/' \
+    -e 's/(\* IANA \*)/let aliases = [/' \
+    -e '$ i] ;; List.iter (fun (a,b) -> alias a b) aliases' \
+    public/charEncoding.ml.orig > public/charEncoding.ml
+
 
 %build
 ./configure --prefix=%{_prefix} --datadir=%{_datadir} --libdir=%{_libdir}
@@ -120,6 +150,11 @@ rm -rf $RPM_BUILD_ROOT
 
 
 %changelog
+* Wed May 30 2012 Richard W.M. Jones <rjones@redhat.com> - 0.8.3-4
+- Remove ExcludeArch ppc64.
+- Add sed hack to reduce size of long entry function which breaks
+  ppc64 code generator.  See comment in spec file for full details.
+
 * Sat May 19 2012 Richard W.M. Jones <rjones@redhat.com> - 0.8.3-2
 - Include workaround for segfault in gen_mappings.ml on ARM.
 - Bump release and rebuild for new OCaml on ARM.