help with alarm code

Try this out there is no debounce of the pin Interrupt 0 is digital pin 2 on the Uno baord

#include <SPI.h> // needed in Arduino 0019 or later
#include <Ethernet.h>
#include <Twitter.h>

// The includion of EthernetDNS is not needed in Arduino IDE 1.0 or later.
// Please uncomment below in Arduino IDE 0022 or earlier.
//#include <EthernetDNS.h>

//const int ledPin = 3;
int ledState = LOW;

// Ethernet Shield Settings
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };

// If you don't specify the IP address, DHCP is used(only in Arduino 1.0 or later).
byte ip[] = { 192, 168, 2, 250 };

// Your Token to Tweet (get it from http://arduino-tweet.appspot.com/)
Twitter twitter("1220261654-BPUYlMFTyfs5ooSFSA62C57Ujeqnr9hdn7PARZm");
// you shouldn't post your token we could post on your Twitter account with this info...

// Message to post


void setup()
{
  digitalWrite(2, HIGH); //turn on internall pullup resistor
  attachInterrupt(0, ExtInt0Fall, FALLING); // there is no debouce of this pin
  delay(1000);
  Ethernet.begin(mac);
  // or you can use DHCP for autoomatic IP address configuration.
  // Ethernet.begin(mac);
  Serial.begin(9600);
  Serial.println("connecting ...");
  char msg[]="que odes";
}

void loop()
{
  if (ledState == HIGH)
    {
      ledState = LOW;
      int cont=0; // ? what is this for??
      Serial.println("High now");   
      delay(1000);
      if (twitter.post(msg)) 
        {
          // Specify &Serial to output received response to Serial.
          // If no output is required, you can just omit the argument, e.g.
          // int status = twitter.wait();
          int status = twitter.wait(&Serial);
          if (status == 200) 
            {
              Serial.println("OK.");
            }
          else
            {
              Serial.print("failed : code ");
              Serial.println(status);
            }
        }
      else 
        Serial.println("connection failed.");
    }
}

void ExtInt0Fall()
{
  ledState = HIGH;
}