Send data from Sensor

Projects Programming
5

I have two programs,the first:

#include <PinChangeInt.h>
#define DATA 8

int cont=0;
void setup() {
  Serial.begin(9600);
  pinMode(DATA, INPUT);
  PCintPort::attachInterrupt(DATA,&cambio,FALLING);
}
void loop()
{
  Serial.println(cont);//to see the serial monitor outputs
  delay(800);
}
void cambio() {
cont++;
}

reads interrupts from a photoelectric sensor in Pin 8 connected to GSM Shield and with the second program(GSMPachubeClient from examples Arduino ide) send the interrupts stored in a variable(cont in this case ) to Xively web or another store data on web.The problem comes when i use <PinChangeInt.h> and <GSM.h> together in the two programs union.
Thanks