[Exim] Problems building SMTP Auth support on RH 7.2

I'm having the strangest issues in trying to get SMTP AUTH working on
my Red Hat 7.2 machine, running Exim 4.05.

I thought I had built the binary just fine with SMTP Authentication
support with these directives uncommented in Local/Makefile:

AUTH_CRAM_MD5=yes
AUTH_PLAINTEXT=yes
AUTH_SPA=yes

Now it doesn't appear as if SMTP Auth is supported. I've searched all
over the archives and read all the resources I can, but maybe I'm
still not doing this correctly. Should the EHLO command show AUTH
support even when the runtime configuration hasn't been properly
configured? When I issue the EHLO command, I can't see any kind of
SMTP AUTH support.

[root@radius1 exim-4.05]# telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 mail.foo.com ESMTP Exim 4.05 Mon, 17 Jun 2002 20:03:30 -0500
EHLO client
250-mail.foo.com Hello client [127.0.0.1]
250-SIZE 52428800
250-PIPELINING
250 HELP
AUTH
504 authentication mechanism not supported


When I try to add an Authenticator in the configuration file, and
re-start exim, I get an error:

Starting exim: 2002-06-17 20:10:36 Exim configuration error in line 260:
error in ACL: unknown ACL verb in "driver = plaintext"


What am I missing? For now I'm just trying to get binary support for
SMTP Auth so that I can see it's there.

I'm dealing with another
problem in that my Red Hat System doesn't have the PAM header files as
well: "call_pam.c:25:31: security/pam_appl.h: No such file or
directory". I wouldn't be surprised if there was some other Gremlin
lurking about here....

Any help appreciated.
-Jason