usb stick mount problem

Hi all,

When I plug a USB memory stick in my MINI2440, and try  mount
it, I receive an "Invalid argument" error.

[root@ahmet /dev]# ls
1-1                 root                tty42
adc                 rtc                 tty43
audio               rtc0                tty44
backlight           sda                 tty45
buttons             sg0                 tty46
camera              shm                 tty47
console             timer               tty48

[root@ahmet /dev]# mount /dev/sda /mnt      
yaffs: dev is 8388608 name is "sda"
yaffs: passed flags ""
yaffs: Attempting MTD mount on 8.0, "sda"
yaffs: dev is 8388608 name is "sda"
yaffs: passed flags ""
yaffs: Attempting MTD mount on 8.0, "sda"
FAT: utf8 is not a recommended IO charset for FAT filesystems, filesystem
will !
mount: mounting /dev/sda on /mnt failed: Invalid argument                  
    


The stick is 8 GB FAT32; 
if you can help me this problem,I am very happy. 

Thanks in advance!

Check first, if your kernel has support for the FAT filesystem (must be
listed in '/proc/filesystems'). If not, you need a new kernel with FAT
enabled, or maybe just to load a kernel module for FAS support. If yes, try
to mount it with the additinal parameter "-t vfat"

thanks 
I used 1gb sd card now correctly mounting. I don't know why my USB(kingston
8gb) hasn't mounted. I think may not support USB or when I debugged the
kernel I saw something as max 4gb supported. I don't remember exactly. 
another my problem . I can use gpio control in console but ı don't
know to use gpio in Qt widget project. I need some tutorial and example
project.
other problem how I count gpio number.