Rebuilding 6.5.3 RPMs

I need to apply a patch to version 6.5.3 (compare function for int4), and update Postgres on many machines.
Since I use RedHat, the best way to do that is to recreate the RPMs for the 6.5.3, with the patch applied... The problem is that postgresql-6.5.3-3.src.rpm found on ftp://ftp.postgresql.org/pub/SRPMS/ doesn't rebuild.

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[root(at)fleurance SPECS]# rpm --rebuild /home/nhuillard/tmp/postgresql-6.5.3-3.src.rpm
...
+ pushd src/interfaces
/usr/src/redhat/BUILD/postgresql-6.5.3/src/interfaces /usr/src/redhat/BUILD/postgresql-6.5.3
+ mkdir -p /var/tmp/postgresql-root/usr/lib/pgsql/perl5
+ cp -a perl5/test.pl perl5/eg /var/tmp/postgresql-root/usr/lib/pgsql/perl5
+ mkdir -p /var/tmp/postgresql-root/usr/lib/pgsql/python
+ cp -a python/tutorial /var/tmp/postgresql-root/usr/lib/pgsql/python
+ popd
/usr/src/redhat/BUILD/postgresql-6.5.3
+ mv /var/tmp/postgresql-root/usr/odbcinst.ini /var/tmp/postgresql-root/usr/lib/pgsql
+ pushd src/bin
/usr/src/redhat/BUILD/postgresql-6.5.3/src/bin /usr/src/redhat/BUILD/postgresql-6.5.3
+ install -m 755 pgaccess/pgaccess /var/tmp/postgresql-root/usr/bin
install: pgaccess/pgaccess: No such file or directory
Bad exit status from /var/tmp/rpm-tmp.46483 (%install)
--------------------------------------------------------------------

I know the simple rebuild won't apply that patch, and also tried the following with the same result. I even edited the SPEC file to delete the install phase of pgaccess, and went just to the end of the install stage :
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[root(at)fleurance SPECS]# rpm -ba postgresql-6.5.3-3.spec
...
Requires: postgresql
Processing files: postgresql-test
Finding provides...
Finding requires...
Provides: autoinc.so refint.so regress.so
Requires: postgresql /bin/csh /bin/sh /usr/bin/perl /usr/bin/python
--------------------------------------------------------------------
... and no RPM file anywhere...

Does anyone have a clue on how to do that, what option to feed RPM, or what to download, and where to store it ?

TIA

Nicolas Huillard