problem with mounting NTFS filesystem on linux

[Alok Pandey <alok rhct gmail com>]

Hi all,
i am getting problem while mounting  150Gb of ntfs partition in linux 
in rw mode. The mount command shows that it mounted in rw mode , but 
when ever i tried to make a dir or file ( as unprivileged user or root) 
it shows permission denied , filesystem in ro mode.

os : Centos 4.3 final 2.6.20.1 (kernel compiled with ntfs support option).

plz help me If any one have face this problem before ?
Any suggestion is welcome 

thanks
--
alok