diff --git a/g10/ChangeLog b/g10/ChangeLog
index 0e238c41b..04d1aa494 100644
--- a/g10/ChangeLog
+++ b/g10/ChangeLog
@@ -1,5 +1,14 @@
 2002-11-23  David Shaw  <dshaw@jabberwocky.com>
 
+	* g10.c (add_notation_data): Disallow notation names that do not
+	contain a '@', unless --expert is set.  This is to help prevent
+	people from polluting the (as yet unused) IETF namespace.
+
+	* main.h: Comments about default algorithms.
+
+	* photoid.c (image_type_to_string): Comments about 3-letter file
+	extensions.
+
 	* encode.c (encode_simple), passphrase.c (passphrase_to_dek),
 	sign.c (sign_symencrypt_file): Use --s2k-digest-algo for
 	passphrase mangling rather than --digest-algo.
diff --git a/g10/g10.c b/g10/g10.c
index b6154dd14..3fa6547bf 100644
--- a/g10/g10.c
+++ b/g10/g10.c
@@ -2812,6 +2812,7 @@ add_notation_data( const char *string, int which )
     STRLIST sl,*notation_data;
     int critical=0;
     int highbit=0;
+    int saw_at=0;
 
     if(which)
       notation_data=&opt.cert_notation_data;
@@ -2823,13 +2824,29 @@ add_notation_data( const char *string, int which )
 	string++;
     }
 
-    for( s=string ; *s != '='; s++ ) {
-	if( !*s || (*s & 0x80) || (!isgraph(*s) && !isspace(*s)) ) {
+    /* If and when the IETF assigns some official name tags, we'll
+       have to add them here. */
+
+    for( s=string ; *s != '='; s++ )
+      {
+	if( *s=='@')
+	  saw_at=0;
+
+	if( !*s || (*s & 0x80) || (!isgraph(*s) && !isspace(*s)) )
+	  {
 	    log_error(_("a notation name must have only printable characters "
 			"or spaces, and end with an '='\n") );
 	    return;
-	}
-    }
+	  }
+      }
+
+    if(!saw_at && !opt.expert)
+      {
+	log_error(
+	        _("a user notation name must contain the '@' character\n"));
+	return;
+      }
+
     /* we only support printable text - therefore we enforce the use
      * of only printable characters (an empty value is valid) */
     for( s++; *s ; s++ ) {
diff --git a/g10/main.h b/g10/main.h
index 0365ed557..a1aff3afb 100644
--- a/g10/main.h
+++ b/g10/main.h
@@ -25,8 +25,10 @@
 #include "cipher.h"
 #include "keydb.h"
 
+/* It could be argued that the default cipher should be 3DES rather
+   than CAST5, and the default compression should be 0
+   (i.e. uncompressed) rather than 1 (zip). */
 #define DEFAULT_CIPHER_ALGO   CIPHER_ALGO_CAST5
-#define DEFAULT_PUBKEY_ALGO   PUBKEY_ALGO_ELGAMAL
 #define DEFAULT_DIGEST_ALGO   DIGEST_ALGO_SHA1
 #define DEFAULT_COMPRESS_ALGO 1
 
diff --git a/g10/photoid.c b/g10/photoid.c
index cb95754fa..7f6b8be7c 100644
--- a/g10/photoid.c
+++ b/g10/photoid.c
@@ -189,8 +189,9 @@ int parse_image_header(const struct user_attribute *attr,byte *type,u32 *len)
 
 /* style==0 for extension, 1 for name, 2 for MIME type.  Remember that
    the "name" style string could be used in a user ID name field, so
-   make sure it is not too big (see
-   parse-packet.c:parse_attribute). */
+   make sure it is not too big (see parse-packet.c:parse_attribute).
+   Extensions should be 3 characters long for the best cross-platform
+   compatibility. */
 char *image_type_to_string(byte type,int style)
 {
   char *string;
@@ -288,7 +289,7 @@ void show_photos(const struct user_attribute *attrs,
 	/* Make the filename.  Notice we are not using the image
            encoding type for more than cosmetics.  Most external image
            viewers can handle a multitude of types, and even if one
-           cannot understand a partcular type, we have no way to know
+           cannot understand a particular type, we have no way to know
            which.  The spec permits this, by the way. -dms */
 
 #ifdef USE_ONLY_8DOT3