does anybody know of a software through which we can send free interational sms from a comp to a mobile?

Answer 1

No i dont, however if you have a internet capable mobile see www.skype.com as an option for downloading to the phone.
the software is free to use. however on a mobile you would pay the data transfer rate your operator set for standard internet access.
you could always try www.majorgeek.com to see if there is anything listed on there suitable for the job.

Answer 2

If you know the name of the telephone service then maybe you could go to that website and see if it will let you send a text.