"sending sms" problem...

hi all..
can any one help me in sending an sms from my mobile through a c#.net program?

i kno there is a class called
class to send an SMS
but in my program i cannot add this class

do i need to import some dll to get this class working?
or am i missing something?

my application is in c#.net and it is for windows mobile 5 pocket pc
my sdk is for windows mobile 5. and i would like to kno if an application developed so works in windows mobile 6 also.

re: "sending sms" problem...

sorry for the question above i've got the solution.
it was because of missing a dll.