diff --git a/lib/libalpm/be_sync.c b/lib/libalpm/be_sync.c
index ef0f1ef4..5477eff4 100644
--- a/lib/libalpm/be_sync.c
+++ b/lib/libalpm/be_sync.c
@@ -70,7 +70,6 @@ static int sync_db_validate(alpm_db_t *db)
 {
 	alpm_siglevel_t level;
 	const char *dbpath;
-	alpm_siglist_t *siglist;
 
 	if(db->status & DB_STATUS_VALID || db->status & DB_STATUS_MISSING) {
 		return 0;
@@ -101,16 +100,26 @@ static int sync_db_validate(alpm_db_t *db)
 	level = alpm_db_get_siglevel(db);
 
 	if(level & ALPM_SIG_DATABASE) {
-		if(_alpm_check_pgp_helper(db->handle, dbpath, NULL,
+		int retry, ret;
+		do {
+			retry = 0;
+			alpm_siglist_t *siglist;
+			ret = _alpm_check_pgp_helper(db->handle, dbpath, NULL,
 					level & ALPM_SIG_DATABASE_OPTIONAL, level & ALPM_SIG_DATABASE_MARGINAL_OK,
-					level & ALPM_SIG_DATABASE_UNKNOWN_OK, &siglist)) {
-			db->handle->pm_errno = ALPM_ERR_DB_INVALID_SIG;
+					level & ALPM_SIG_DATABASE_UNKNOWN_OK, &siglist);
+			if(ret) {
+				retry = _alpm_process_siglist(db->handle, db->treename, siglist,
+						level & ALPM_SIG_DATABASE_OPTIONAL, level & ALPM_SIG_DATABASE_MARGINAL_OK,
+						level & ALPM_SIG_DATABASE_UNKNOWN_OK);
+			}
 			alpm_siglist_cleanup(siglist);
 			free(siglist);
+		} while(retry);
+
+		if(ret) {
+			db->handle->pm_errno = ALPM_ERR_DB_INVALID_SIG;
 			return 1;
 		}
-		alpm_siglist_cleanup(siglist);
-		free(siglist);
 	}
 
 valid:
diff --git a/lib/libalpm/signing.c b/lib/libalpm/signing.c
index 7e05a237..e1b6452c 100644
--- a/lib/libalpm/signing.c
+++ b/lib/libalpm/signing.c
@@ -507,6 +507,69 @@ int _alpm_check_pgp_helper(alpm_handle_t *handle, const char *path,
 	return ret;
 }
 
+int _alpm_process_siglist(alpm_handle_t *handle, const char *identifier,
+		alpm_siglist_t *siglist, int optional, int marginal, int unknown)
+{
+	size_t i;
+	int retry = 0;
+
+	if(!optional && siglist->count == 0) {
+		_alpm_log(handle, ALPM_LOG_ERROR,
+				_("%s: missing required signature\n"), identifier);
+	}
+
+	for(i = 0; i < siglist->count; i++) {
+		alpm_sigresult_t *result = siglist->results + i;
+		const char *name = result->key.uid ? result->key.uid : result->key.fingerprint;
+		switch(result->status) {
+			case ALPM_SIGSTATUS_VALID:
+			case ALPM_SIGSTATUS_KEY_EXPIRED:
+				switch(result->validity) {
+					case ALPM_SIGVALIDITY_FULL:
+						break;
+					case ALPM_SIGVALIDITY_MARGINAL:
+						if(!marginal) {
+							_alpm_log(handle, ALPM_LOG_ERROR,
+									_("%s: signature from \"%s\" is marginal trust\n"),
+									identifier, name);
+						}
+						break;
+					case ALPM_SIGVALIDITY_UNKNOWN:
+						if(!unknown) {
+							_alpm_log(handle, ALPM_LOG_ERROR,
+									_("%s: signature from \"%s\" is unknown trust\n"),
+									identifier, name);
+						}
+						break;
+					case ALPM_SIGVALIDITY_NEVER:
+						_alpm_log(handle, ALPM_LOG_ERROR,
+								_("%s: signature from \"%s\" should never be trusted\n"),
+								identifier, name);
+						break;
+				}
+				break;
+			case ALPM_SIGSTATUS_KEY_UNKNOWN:
+				/* TODO import key here */
+				_alpm_log(handle, ALPM_LOG_ERROR,
+						_("%s: key \"%s\" is unknown\n"),
+						identifier, name);
+				break;
+			case ALPM_SIGSTATUS_SIG_EXPIRED:
+				_alpm_log(handle, ALPM_LOG_ERROR,
+						_("%s: signature from \"%s\" is expired\n"),
+						identifier, name);
+				break;
+			case ALPM_SIGSTATUS_INVALID:
+				_alpm_log(handle, ALPM_LOG_ERROR,
+						_("%s: signature from \"%s\" is invalid\n"),
+						identifier, name);
+				break;
+		}
+	}
+
+	return retry;
+}
+
 /**
  * Check the PGP signature for the given package file.
  * @param pkg the package to check
diff --git a/lib/libalpm/signing.h b/lib/libalpm/signing.h
index ee4a94a0..315d6059 100644
--- a/lib/libalpm/signing.h
+++ b/lib/libalpm/signing.h
@@ -24,9 +24,12 @@
 char *_alpm_sigpath(alpm_handle_t *handle, const char *path);
 int _alpm_gpgme_checksig(alpm_handle_t *handle, const char *path,
 		const char *base64_sig, alpm_siglist_t *result);
+
 int _alpm_check_pgp_helper(alpm_handle_t *handle, const char *path,
 		const char *base64_sig, int optional, int marginal, int unknown,
 		alpm_siglist_t **sigdata);
+int _alpm_process_siglist(alpm_handle_t *handle, const char *identifier,
+		alpm_siglist_t *siglist, int optional, int marginal, int unknown);
 
 #endif /* _ALPM_SIGNING_H */