Merged the fix for bug 176667 on the NSS_3_6_BRANCH.

git-svn-id: svn://10.0.0.236/branches/NSS_3_6_BRANCH@134498 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/security/nss/lib/certhigh/certvfy.c

@@ -388,6 +388,9 @@ loser:
 	    return STAN_GetCERTCertificate(chain[1]); /* return the 2nd */
 	}
     } else {
+	if (chain[0]) {
+	    CERT_DestroyCertificate(cert);
+	}
 	PORT_SetError (SEC_ERROR_UNKNOWN_ISSUER);
     }
     return NULL;