sim900 to mobile phone

I had purchase arduino uno rev3 and icomsat v1.1 sim900. I want to use these board and shield to send sms to my mobile phone. The coding i tested is from the example codes of the libraries. The TX,RX pin i used same as what had shown in the libraries(pin2&3). I also supply 12v/1.2A to my gsm shield to boot it up. So far the code has no problem but the problem is i did not received any sms from the gsm shield. Anyone know where is my mistake?

libraries I dl from: http://code.google.com/p/gsm-shield-arduino/

Result I get from serialmonitor:
GSM Shield testing.
status=READY
SMS sent OK

my code:

#include "SIM900.h"
#include <SoftwareSerial.h>

#include "sms.h"
SMSGSM sms;

int numdata;
boolean started=false;
char smsbuffer[160];
char n[20];

void setup() 
{
  Serial.begin(9600);
  Serial.println("GSM Shield testing.");
  
  if (gsm.begin(2400)){
    Serial.println("\nstatus=READY");
    started=true;  
  }
  else Serial.println("\nstatus=IDLE");
  
  if(started){
    if (sms.SendSMS("+6016811800", "Arduino SMS"))        //i had double check my country code is correct.
      Serial.println("\nSMS sent OK");
  }
};

void loop() 
{
  if(started){
    if(gsm.readSMS(smsbuffer, 160, n, 20))
    {
      Serial.println(n);
      Serial.println(smsbuffer);
    }
    delay(1000);
  }
};

Hi, just a rough guess, are you from Malaysia? if you are i think you keyed your phone number wrongly, u are missing a digit. it should be like 016 811 800X

hi desmond, opps.. typo for the phone number. i can confirm that my country code and phone number are correct. just wonder why i cant received any sms.