Setting Pullup/Pulldown Resistors

I’m think I’m a little bit out of luck…

today I tried to program Pull UP/DOWN resitors of the pins but it doesn’t worked for me. Here is my example code where I try to pullup the internal resistor of GPIO49. Other pins doesn’t worked also …

[code]#include “vmsystem.h”
#include “vmthread.h”
#include “ResID.h”
#include “vmdcl.h”
#include “vmdcl_gpio.h”

VMINT32 main_thread(VM_THREAD_HANDLE thread_handle, void *user_data)
{
VM_DCL_HANDLE gpio_handle = vm_dcl_open(VM_DCL_GPIO, 49);
vm_dcl_control(gpio_handle, VM_DCL_GPIO_COMMAND_SET_MODE_0, NULL);
vm_dcl_control(gpio_handle, VM_DCL_GPIO_COMMAND_SET_DIRECTION_IN, NULL);
vm_dcl_control(gpio_handle, VM_DCL_GPIO_COMMAND_ENABLE_PULL, NULL);
vm_dcl_control(gpio_handle, VM_DCL_GPIO_COMMAND_SET_PULL_HIGH, NULL);

while(1)
{
	vm_thread_sleep(1000);
}

return 0;

}

void vm_main(void)
{
//Eine Sekunde warten um dem System Zeit zu geben sich zu aktivieren.
vm_thread_sleep(1000);

//System Callback Funktion wird hier registriert.
VM_THREAD_HANDLE main_handle;
main_handle = vm_thread_create(main_thread, NULL, 200);

}
[/code]

I just wonder because in the technical datasheet of the MTK2502A almost every pin is programmable to Pull UP/DOWN in mode 0
http://labs.mediatek.com/fileMedia/download/a6883a0a-710e-42cc-8c53-c1ae990d83e3