Index: b/g10/keydb.h
===================================================================
--- b/g10/keydb.h
+++ b/g10/keydb.h
@@ -249,12 +249,21 @@
    for the user ID node.  */
 gpg_error_t keydb_get_keyblock (KEYDB_HANDLE hd, KBNODE *ret_kb);
 
-/* Replace the currently selected keyblock (i.e., the last result
-   returned by keydb_search) with the key block in KB.
+/* Update the keyblock KB (i.e., extract the fingerprint and find the
+   corresponding keyblock in the keyring).
 
    This doesn't do anything if --dry-run was specified.
 
-   Returns 0 on success.  Otherwise, it returns an error code.  */
+   Returns 0 on success.  Otherwise, it returns an error code.  Note:
+   if there isn't a keyblock in the keyring corresponding to KB, then
+   this function returns GPG_ERR_VALUE_NOT_FOUND.
+
+   This function selects the matching record and modifies the current
+   file position to point to the record just after the selected entry.
+   Thus, if you do a subsequent search using HD, you should first do a
+   keydb_search_reset.  Further, if the selected record is important,
+   you should use keydb_push_found_state and keydb_pop_found_state to
+   save and restore it.  */
 gpg_error_t keydb_update_keyblock (KEYDB_HANDLE hd, kbnode_t kb);
 
 /* Insert a keyblock into one of the underlying keyrings or keyboxes.
Index: b/g10/keydb.c
===================================================================
--- b/g10/keydb.c
+++ b/g10/keydb.c
@@ -1386,6 +1386,12 @@
 keydb_update_keyblock (KEYDB_HANDLE hd, kbnode_t kb)
 {
   gpg_error_t err;
+  PKT_public_key *pk = kb->pkt->pkt.public_key;
+  KEYDB_SEARCH_DESC desc;
+  size_t len;
+
+  assert (kb);
+  assert (kb->pkt->pkttype == PKT_PUBLIC_KEY);
 
   if (!hd)
     return gpg_error (GPG_ERR_INV_ARG);
@@ -1393,9 +1399,6 @@
   kid_not_found_flush ();
   keyblock_cache_clear (hd);
 
-  if (hd->found < 0 || hd->found >= hd->used)
-    return gpg_error (GPG_ERR_VALUE_NOT_FOUND);
-
   if (opt.dry_run)
     return 0;
 
@@ -1403,6 +1406,21 @@
   if (err)
     return err;
 
+  memset (&desc, 0, sizeof (desc));
+  fingerprint_from_pk (pk, desc.u.fpr, &len);
+  if (len == 20)
+    desc.mode = KEYDB_SEARCH_MODE_FPR20;
+  else if (len == 16)
+    desc.mode = KEYDB_SEARCH_MODE_FPR16;
+  else
+    log_bug ("%s: Unsupported key length: %zd\n", __func__, len);
+
+  keydb_search_reset (hd);
+  err = keydb_search (hd, &desc, 1, NULL);
+  if (err)
+    return gpg_error (GPG_ERR_VALUE_NOT_FOUND);
+  assert (hd->found >= 0 && hd->found < hd->used);
+
   switch (hd->active[hd->found].type)
     {
     case KEYDB_RESOURCE_TYPE_NONE: