[PIC32] undefined reference to `vTaskDelay’

hi,
i have a big problem with a file who contain this function :
void demon_heure(void *ptr)
{
    while(1)
    {
        heure_maj();    
        vTaskDelay(250/portTICK_RATE_MS);
    }   
}
in unique file, c32 return me error :
Heure.c:16: undefined reference to `vTaskDelay’ in main file, all is OK. the include section  of all theses files are :
#include "recepteur.h"
#include "string.h"
#include "stdlib.h"
#include "FSIO.h"
#include "ImageDecoder.h"
in recepteur.h :
#include "FreeRTOSConfig.h"
#include "FreeRTOS.h"
#include "task.h"
what is the problem ???

[PIC32] undefined reference to `vTaskDelay’

all is ok,
in main file, i put theses lines under while(1) function,
c32 does not compile code after this function.
my problem is a mismatch config.

[PIC32] undefined reference to `vTaskDelay’

To use vTaskDelay you need to have
#include "FreeRTOS.h"
#include "task.h"
You do not need to include FreeRTOSConfig.h because it is included inside FreeRTOS.h.