Document NSS requirement, revise obsolete comment in macros.in

INSTALL

@@ -5,6 +5,9 @@ The zlib library for compression support. You might also need/want
 the zip executable for java jar dependency analysis. All available from
     http://www.gzip.org/zlib/
 
+The NSS library for encryption. This is available from 
+    http://www.mozilla.org/projects/security/pki/nss/
+
 The Berkeley DB >= 4.3.x (4.5.x or newer recommended). RPM includes an
 internal copy which is used by default, but if you want to use an external
 BDB (--with-external-db) it's available at

macros.in

@@ -651,7 +651,7 @@ print (t)\
 	pgps +batchmode=on +verbose=0 +armor=off \
 	"+myname=%{_pgp_name}" -b %{__plaintext_filename} -o %{__signature_filename}
 
-# XXX rpm-4.1 verifies signatures using beecrypt.
+# XXX rpm >= 4.1 verifies signatures internally
 #%__gpg_verify_cmd		%{__gpg} \
 #	gpg --batch --no-verbose --verify --no-secmem-warning \
 #	%{__signature_filename} %{__plaintext_filename}