Library conflict (vector_9, 10 & 11)

Hello all,

I have a problem using the Software Serial and GSM libraries at the same time, individually they work without problems.
I am using a mega 2560 and know that I should use the hardware serials, but it doens't work with the shields so I'm stuck using software serial....
I already tried using various softserial alternatives such as altserial and neoSWserial but without success.
What i am trying to do is use an RS232 shield to read data from a serial device and send it to my server over GPRS with an arduino antenova GSM shield (v2) since it is an off grid system.

I have attached the first lines of code (full code is over 9000! limit) and the error message.
Does anyone know how to fix the vector issues or should i just use two arduino's and let them communicate by i2c?

//#include <NeoSWSerial.h>
#include <SoftwareSerial.h>
#include <stdint.h>
#include <Wire.h>   //I2C for sensor and screen
#include <LiquidCrystal_I2C.h>
#include <GSM.h>

#define XcomSerial Serial1
//#define rxPin 11
//#define txPin 5
//NeoSWSerial XcomSerial(rxPin,txPin);
LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);  // Set the LCD I2C address

// PIN Number for the SIM
#define PINNUMBER ""    // replace with your PIN
// APN data
#define GPRS_APN       "apn" // replace with our GPRS APN
#define GPRS_LOGIN     "user"    // replace with your GPRS login
#define GPRS_PASSWORD  "pass" // replace with your GPRS password

// initialize the library instances
GSM gsmAccess;
GSMClient client;
GPRS gprs;
GSM_SMS sms;

// URL, path & port 
char server[] = "server";
char path[] = "/main page";
int port = 80; // port 80 is the default for HTTP

This is the fault message:

Arduino: 1.8.4 (Windows 10), Board:"Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)"

libraries\GSM\GSM3SoftSerial.cpp.o (symbol from plugin): In function `GSM3SoftSerial::spaceAvailable()':

(.text+0x0): multiple definition of `__vector_9'

libraries\SoftwareSerial\SoftwareSerial.cpp.o (symbol from plugin):(.text+0x0): first defined here

c:/users/ategjalt/appdata/local/arduino15/packages/arduino/tools/avr-gcc/4.9.2-atmel3.5.4-arduino2/bin/../lib/gcc/avr/4.9.2/../../../../avr/bin/ld.exe: Disabling relaxation: it will not work with multiple definitions

libraries\GSM\GSM3SoftSerial.cpp.o (symbol from plugin): In function `GSM3SoftSerial::spaceAvailable()':

(.text+0x0): multiple definition of `__vector_10'

libraries\SoftwareSerial\SoftwareSerial.cpp.o (symbol from plugin):(.text+0x0): first defined here

libraries\GSM\GSM3SoftSerial.cpp.o (symbol from plugin): In function `GSM3SoftSerial::spaceAvailable()':

(.text+0x0): multiple definition of `__vector_11'

libraries\SoftwareSerial\SoftwareSerial.cpp.o (symbol from plugin):(.text+0x0): first defined here

collect2.exe: error: ld returned 1 exit status

exit status 1
Fout bij het compileren voor board Arduino/Genuino Mega or Mega 2560

Does anyone know how to fix the vector issues

You have to stop using one of the libraries that uses the vectors. The stupid shits that created the GSM serial class re-developed, instead of inheriting from, SoftwareSerial, so you can't use them both at the same time.

You COULD bend the pins on the RS232 shield that are forcing you to use SoftwareSerial, and then connect the bent pins to other (hardware serial) pins.