Add documentation for additional packages, remove unneeded package libcrypt-openssl-random-perl

setup/spamassassin.sh

@@ -16,9 +16,14 @@ source setup/functions.sh # load our functions
 # ----------------------------------------
 
 # Install packages.
+# libmail-dkim-perl is needed to make the spamassassin DKIM module work.
+# For more information see Debian Bug #689414:
+# https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=689414
+# libcrypt-openssl-bignum-perl and libcrypt-openssl-rsa-perl are
+# direct dependencies of libmail-dkim-perl.
 echo "Installing SpamAssassin..."
 apt_install spampd razor pyzor dovecot-antispam libcrypt-openssl-bignum-perl \
-        libcrypt-openssl-rsa-perl libmail-dkim-perl libcrypt-openssl-random-perl
+        libcrypt-openssl-rsa-perl libmail-dkim-perl
 
 # Allow spamassassin to download new rules.
 tools/editconf.py /etc/default/spamassassin \