Building Tripwire RPM on CentOS6

I have been unable to locate a pre-built RPM for Tripwire on CentOS6.

I have tried installing the one from CentOS5, as well as a couple of later Fedora RPMs, but all fail on a dependency on libcrypto.so.6. I DO have the openssl-devel package installed (whence libcrypto.so but not with the trailing .6).

So I tried rpmbuild'ing using the .spec file included in the source distribution from SourceForge.

Either I'm doing something way off base (a distinct possibility) or the .spec file is way out of date. To get it to even build I had to tweak several things:

1. Renamed the source directory from tripwire-2.4.2.2-src to just plain tripwire-2.4.2.2 because that's what the generated temp script seems to expect;
2. Downloaded the required tripwire-siggen-man8.patch and placed it in rpmbuild/SOURCES where the script wants it;
3. created empty License-Issues and tripwire.gif, also in rpmbuild/SOURCES, again because the script needed these files to exist

Now I've hit a roadblock I can't get around.

+ cd /home/jhg/rpmbuild/BUILD 
+ cd tripwire-2.4.2.2 
+ /bin/rm -rf /home/jhg/rpmbuild/BUILDROOT/tripwire-2.4.2.2-1.el6.x86_64 
+ post
/var/tmp/rpm-tmp.tf9QWJ: line 31: post: command not found error: Bad
exit status from /var/tmp/rpm-tmp.tf9QWJ (%clean) 

I think the line post should be a comment, as the line below it in the script does some post install configuration.

However, with this many tweaks I'm more inclined to believe I went down a wrong path.

Question: Is it possible to build a Tripwire 2.4.2.2 RPM on CentOS6 with the .spec file in the source distribution as downloaded, and if so, how is this accomplished.