diff --git a/include/ulib/net/client/smtp.h b/include/ulib/net/client/smtp.h
index 5315f1af..c859aac2 100644
--- a/include/ulib/net/client/smtp.h
+++ b/include/ulib/net/client/smtp.h
@@ -69,6 +69,8 @@ public:
       GREET                       = 220, // greeting from server
       GOODBYE                     = 221, // server acknolages quit
       SUCCESSFUL                  = 250, // command successful
+      AUTHENTICATED               = 235, // Authentication successful
+      CHALLENGE                   = 334, // Login Credential Reqested
       READYDATA                   = 354, // server ready to receive data
       UNAVAILABLE                 = 450, // service not available
       ERR_PROCESSING              = 451, // error in processing
@@ -116,7 +118,8 @@ public:
    UString getRecipientAddress() const { return rcptoAddress; }
 
    bool startTLS();
-   bool sendMessage(bool secure = false);
+   bool authLogin(const UString* username, const UString* password);
+   bool sendMessage(bool secure = false, const UString* username = U_NULLPTR, const UString* password = U_NULLPTR);
 
    void setDomainName(      const UString& name)      { domainName     = name; }
    void setMessageBody(     const UString& message)   { messageBody    = message; }
diff --git a/src/ulib/net/client/smtp.cpp b/src/ulib/net/client/smtp.cpp
index aab2233b..86461fdf 100644
--- a/src/ulib/net/client/smtp.cpp
+++ b/src/ulib/net/client/smtp.cpp
@@ -172,8 +172,10 @@ U_NO_EXPORT void USmtpClient::setStateFromResponse()
       {
       case -1:              state = CERROR; break;
       case GREET:           state = LOG_IN; break;
+      case CHALLENGE:       state = LOG_IN; break;
       case GOODBYE:         state = QUIT;   break;
       case READYDATA:       state = DATA;   break;
+      case AUTHENTICATED:   response = SUCCESSFUL;  break;
 
       case SUCCESSFUL:
          {
@@ -237,9 +239,31 @@ bool USmtpClient::startTLS()
    U_RETURN(false);
 }
 
+bool USmtpClient::authLogin(const UString* username, const UString* password)
+{
+  U_TRACE_NO_PARAM(0, "USmtpClient::auth_login()")
+  syncCommand(U_CONSTANT_TO_PARAM("HELO"));
+
+#ifdef USE_LIBSSL
+    if (((USSLSocket*)this)->isSSLActive()
+        && username->isBase64() && password->isBase64()){
+
+      if (syncCommand(U_CONSTANT_TO_PARAM("auth login"))
+          && syncCommand(username->c_str(),username->size())
+          && syncCommand(password->c_str(),password->size())
+          && response == SUCCESSFUL){
+            U_RETURN(true);
+         }
+         }
+#endif
+
+  U_RETURN(false);
+}
+
+
 // Execute an smtp transaction
 
-bool USmtpClient::sendMessage(bool secure)
+bool USmtpClient::sendMessage(bool secure, const UString* username, const UString* password)
 {
    U_TRACE(0, "USmtpClient::sendMessage(%b)", secure)
 
@@ -267,9 +291,18 @@ bool USmtpClient::sendMessage(bool secure)
          {
          U_RETURN(false);
          }
+      else
+         {
+          if(username && password)
+          {
+            if(!authLogin(username,password)){
+              U_RETURN(false);
+            }
+          }
 
       (void) syncCommand(U_CONSTANT_TO_PARAM("ehlo %v"), domainName.rep);
       }
+      }
 
    if (response != SUCCESSFUL) U_RETURN(false);