[Samba] How access time of the same file different within a smbmounted file system?

[Iap, Singuan]

In Windows XP, I share a folder "SHARED_FOLDER".
Then, mount it by using "smbmount"  to  /mnt/SHARED_FOLDER in a Linux box
with smaba 3.0.4

Then, I invoke a stat() call to a file in /mnt/SHARED_FOLDER (in Python):
ex.
$python
>> import os,time
>> s=os.stat('/mnt/SHARED_FOLDER/A_FILE')
>> print s.st_atime ## the access time of  "A_FILE"

On the other hand,
I invoke the same process in local Windows XP,
and the printed s.st_atime are different from the one in above (smbmounted
).

How it comes?
Any hints?

Iap, Singuan
(mtime, ctime are the same, no differences)