Index: b/doc/gpg.texi
===================================================================
--- b/doc/gpg.texi
+++ b/doc/gpg.texi
@@ -2789,9 +2789,20 @@
 
 @item --allow-weak-digest-algos
 @opindex allow-weak-digest-algos
-Signatures made with the broken MD5 algorithm are normally rejected
-with an ``invalid digest algorithm'' message.  This option allows the
-verification of signatures made with such weak algorithms.
+Signatures made with known-weak digest algorithms are normally
+rejected with an ``invalid digest algorithm'' message.  This option
+allows the verification of signatures made with such weak algorithms.
+MD5 is the only digest algorithm considered weak by default.  See also
+@option{--weak-digest} to reject other digest algorithms.
+
+@item --weak-digest @code{name}
+@opindex weak-digest
+Treat the specified digest algorithm as weak.  Signatures made over
+weak digests algorithms are normally rejected. This option can be
+supplied multiple times if multiple algorithms should be considered
+weak.  See also @option{--allow-weak-digest-algos} to disable
+rejection of weak digests.  MD5 is always considered weak, and does
+not need to be listed explicitly.
 
 @item --no-default-keyring
 @opindex no-default-keyring
Index: b/doc/gpgv.texi
===================================================================
--- b/doc/gpgv.texi
+++ b/doc/gpgv.texi
@@ -118,6 +118,14 @@
 
 @include opt-homedir.texi
 
+@item --weak-digest @code{name}
+@opindex weak-digest
+Treat the specified digest algorithm as weak.  Signatures made over
+weak digests algorithms are normally rejected. This option can be
+supplied multiple times if multiple algorithms should be considered
+weak.  MD5 is always considered weak, and does not need to be listed
+explicitly.
+
 @end table
 
 @mansect return value
Index: b/g10/gpg.c
===================================================================
--- b/g10/gpg.c
+++ b/g10/gpg.c
@@ -389,6 +389,7 @@
     oPrintDANERecords,
     oTOFUDefaultPolicy,
     oTOFUDBFormat,
+    oWeakDigest,
 
     oNoop
   };
@@ -749,6 +750,7 @@
   ARGPARSE_s_s (oPersonalCompressPreferences,
                                          "personal-compress-preferences", "@"),
   ARGPARSE_s_s (oFakedSystemTime, "faked-system-time", "@"),
+  ARGPARSE_s_s (oWeakDigest, "weak-digest","@"),
 
   /* Aliases.  I constantly mistype these, and assume other people do
      as well. */
@@ -2208,6 +2210,7 @@
     set_homedir (default_homedir ());
     opt.passphrase_repeat = 1;
     opt.emit_version = 1; /* Limit to the major number.  */
+    opt.additional_weak_digests = NULL;
 
     /* Check whether we have a config file on the command line.  */
     orig_argc = argc;
@@ -3124,6 +3127,9 @@
 	    break;
           case oAgentProgram: opt.agent_program = pargs.r.ret_str;  break;
           case oDirmngrProgram: opt.dirmngr_program = pargs.r.ret_str; break;
+          case oWeakDigest:
+	    additional_weak_digest(pargs.r.ret_str);
+	    break;
 
           case oDisplay:
             set_opt_session_env ("DISPLAY", pargs.r.ret_str);
Index: b/g10/gpgv.c
===================================================================
--- b/g10/gpgv.c
+++ b/g10/gpgv.c
@@ -61,6 +61,7 @@
   oStatusFD,
   oLoggerFD,
   oHomedir,
+  oWeakDigest,
   aTest
 };
 
@@ -78,6 +79,7 @@
                 N_("|FD|write status info to this FD")),
   ARGPARSE_s_i (oLoggerFD, "logger-fd", "@"),
   ARGPARSE_s_s (oHomedir, "homedir", "@"),
+  ARGPARSE_s_s (oWeakDigest, "weak-digest", "@"),
 
   ARGPARSE_end ()
 };
@@ -192,6 +194,9 @@
           log_set_fd (translate_sys2libc_fd_int (pargs.r.ret_int, 1));
           break;
         case oHomedir: opt.homedir = pargs.r.ret_str; break;
+        case oWeakDigest:
+          additional_weak_digest(pargs.r.ret_str);
+          break;
         case oIgnoreTimeConflict: opt.ignore_time_conflict = 1; break;
         default : pargs.err = ARGPARSE_PRINT_ERROR; break;
 	}
Index: b/g10/main.h
===================================================================
--- b/g10/main.h
+++ b/g10/main.h
@@ -69,6 +69,12 @@
   struct groupitem *next;
 };
 
+struct weakhash
+{
+  enum gcry_md_algos algo;
+  struct weakhash *next;
+};
+
 
 /*-- gpg.c --*/
 extern int g10_errors_seen;
@@ -82,6 +88,7 @@
 void print_cipher_algo_note (cipher_algo_t algo);
 void print_digest_algo_note (digest_algo_t algo);
 void print_md5_rejected_note (void);
+void additional_weak_digest (const char* digestname);
 
 /*-- armor.c --*/
 char *make_radix64_string( const byte *data, size_t len );
Index: b/g10/misc.c
===================================================================
--- b/g10/misc.c
+++ b/g10/misc.c
@@ -307,6 +307,10 @@
 void
 print_digest_algo_note (digest_algo_t algo)
 {
+  int deprecated = 0;
+  const enum gcry_md_algos galgo = map_md_openpgp_to_gcry (algo);
+  const struct weakhash *weak;
+  
   if(algo >= 100 && algo <= 110)
     {
       static int warn=0;
@@ -315,14 +319,21 @@
 	  warn=1;
           es_fflush (es_stdout);
 	  log_info (_("WARNING: using experimental digest algorithm %s\n"),
-                    gcry_md_algo_name (algo));
+                    gcry_md_algo_name (galgo));
 	}
     }
-  else if(algo==DIGEST_ALGO_MD5)
+  else if(algo == DIGEST_ALGO_MD5)
+    deprecated = 1;
+  else
+      for (weak = opt.additional_weak_digests; weak != NULL; weak = weak->next)
+        if (weak->algo == galgo)
+          deprecated = 1;
+
+  if (deprecated)
     {
       es_fflush (es_stdout);
       log_info (_("WARNING: digest algorithm %s is deprecated\n"),
-                gcry_md_algo_name (algo));
+                gcry_md_algo_name (galgo));
     }
 }
 
@@ -1676,3 +1687,37 @@
   qbits /= 2;
   return qbits;
 }
+
+
+/* ignore signatures and certifications made over certain digest
+   algorithms by default, MD5 is considered weak.  This allows users
+   to deprecate support for other algorithms as well.
+*/
+void
+additional_weak_digest (const char* digestname)
+{
+  struct weakhash *weak = NULL;
+  const enum gcry_md_algos algo = string_to_digest_algo(digestname);
+
+  if (algo == GCRY_MD_MD5)
+    return; /* MD5 is always considered weak, no need to add it */
+
+  if (algo == GCRY_MD_NONE)
+    {
+      log_error(_("Unknown weak digest '%s'\n"), digestname);
+      return;
+    }
+
+  /* check to ensure it's not already present */
+  for (weak = opt.additional_weak_digests; weak != NULL; weak = weak->next)
+    {
+      if (algo == weak->algo)
+        return;
+    }
+
+  /* add it to the head of the list */
+  weak = xmalloc(sizeof(*weak));
+  weak->algo = algo;
+  weak->next = opt.additional_weak_digests;
+  opt.additional_weak_digests = weak;
+}
Index: b/g10/options.h
===================================================================
--- b/g10/options.h
+++ b/g10/options.h
@@ -170,6 +170,7 @@
   prefitem_t *personal_cipher_prefs;
   prefitem_t *personal_digest_prefs;
   prefitem_t *personal_compress_prefs;
+  struct weakhash *additional_weak_digests;
   int no_perm_warn;
   int no_mdc_warn;
   char *temp_dir;
Index: b/g10/sig-check.c
===================================================================
--- b/g10/sig-check.c
+++ b/g10/sig-check.c
@@ -274,15 +274,18 @@
 {
     gcry_mpi_t result = NULL;
     int rc = 0;
+    const struct weakhash *weak;
 
     if( (rc=do_check_messages(pk,sig,r_expired,r_revoked)) )
         return rc;
 
-    if (sig->digest_algo == GCRY_MD_MD5
-        && !opt.flags.allow_weak_digest_algos)
+    if (!opt.flags.allow_weak_digest_algos)
       {
-        print_md5_rejected_note ();
-        return GPG_ERR_DIGEST_ALGO;
+        if (sig->digest_algo == GCRY_MD_MD5)
+          return GPG_ERR_DIGEST_ALGO;
+        for (weak = opt.additional_weak_digests; weak != NULL; weak = weak->next)
+          if (sig->digest_algo == weak->algo)
+            return GPG_ERR_DIGEST_ALGO;
       }
 
     /* Make sure the digest algo is enabled (in case of a detached