diff --git a/g10/ChangeLog b/g10/ChangeLog
index 5526cb182..c8bbfc62a 100644
--- a/g10/ChangeLog
+++ b/g10/ChangeLog
@@ -1,3 +1,11 @@
+2003-03-24  David Shaw  <dshaw@jabberwocky.com>
+
+	* keydb.h: Err on the side of making an unknown signature a SIG
+	rather than a CERT.
+
+	* import.c (delete_inv_parts): Discard any key signatures that
+	aren't key types (i.e. 0x00, 0x01, etc.)
+
 2003-03-24  Werner Koch  <wk@gnupg.org>
 
 	* Makefile.am: Make use of AM_CFLAGS and AM_LDFLAGS.
diff --git a/g10/import.c b/g10/import.c
index 46162e973..62e15eaa2 100644
--- a/g10/import.c
+++ b/g10/import.c
@@ -1298,6 +1298,14 @@ delete_inv_parts( const char *fname, KBNODE keyblock,
 		       (ulong)keyid[1]);
 	    delete_kbnode( node );
 	}
+	else if( node->pkt->pkttype == PKT_SIGNATURE
+		 && !IS_CERT(node->pkt->pkt.signature))
+	  {
+	    log_error(_("key %08lX: unexpected signature class (0x%02X) -"
+			" skipped\n"),(ulong)keyid[1],
+		      node->pkt->pkt.signature->sig_class);
+	    delete_kbnode(node);
+	  }
 	else if( (node->flag & 4) ) /* marked for deletion */
 	    delete_kbnode( node );
     }
diff --git a/g10/keydb.h b/g10/keydb.h
index 76a96ed76..8416ec8ae 100644
--- a/g10/keydb.h
+++ b/g10/keydb.h
@@ -27,10 +27,9 @@
 #include "cipher.h"
 
 /* What qualifies as a certification (rather than a signature?) */
-#define IS_SIG(s) (((s)->sig_class==0x00) || ((s)->sig_class==0x01) || \
-		   ((s)->sig_class==0x02) || ((s)->sig_class==0x40))
-#define IS_CERT(s) (!IS_SIG(s))
-
+#define IS_CERT(s)       (IS_KEY_SIG(s) || IS_UID_SIG(s) || IS_SUBKEY_SIG(s) \
+                         || IS_KEY_REV(s) || IS_UID_REV(s) || IS_SUBKEY_REV(s))
+#define IS_SIG(s)        (!IS_CERT(s))
 #define IS_KEY_SIG(s)    ((s)->sig_class == 0x1f)
 #define IS_UID_SIG(s)    (((s)->sig_class & ~3) == 0x10)
 #define IS_SUBKEY_SIG(s) ((s)->sig_class == 0x18)
@@ -38,7 +37,6 @@
 #define IS_UID_REV(s)    ((s)->sig_class == 0x30)
 #define IS_SUBKEY_REV(s) ((s)->sig_class == 0x28)
 
-
 struct getkey_ctx_s;
 typedef struct getkey_ctx_s *GETKEY_CTX;