Running cgi-bin programs under AllegroServe

I'm just getting started with Lisp and AllegroServe and could
(desperately) use some help.

I simply want to be able to run a cgi program using AllegroServe.
Anytime that I try to run a program, I get an "HTTP 500 - Internal
server error". I can serve up images and html pages
fine.

Here is my setup:

directory contains (file contents are at end of email):

a.lisp

a.gif

a.pl (755, #!/usr/bin/perl as first line, and runs fine stand-alone
producing: Content-type: text/html\nHello, world!)

Steps:

run lisp (AllegroServe 6.1 - starts server on port 8000 and
publishes files a.gif and a.pl

enter
http://hostname:8000/a.gif a.gif served up properly

enter
http://hostname:8000/a.pl

get HTTP 500 error

Any help would be greatly appreciated.

Bob Clark

a.lisp:

(require :aserve)

(defpackage :http-test

(:use :common-lisp :excl :net.aserve
:net.html.generator))

(in-package :http-test)

(net.aserve::debug-on :info t)

(start :port 8000)

(publish-file :path "/a.gif" :file "a.gif"
:content-type "image/gif")

(publish :path "/a.pl"

:function #'(lambda (req
ent)

(run-cgi-program req ent "/a.pl")))

a.pl:

#!/usr/bin/perl

print "Content-type: text/html\n\n";

print "Hello, world!\n";