Found this nice SDK for the Windows Mobile that can be used with the PC to act as the SMS Server .
The Project is from the MSRIndia and allows the developers to write the SMS Applications using their Windows Mobile and the PC .
The Project also includes a collection of samples that allows the users to use the Excel and send bulk sms.
To run the SMS SDK,the following items are necessary
- windows mobile 5 and above
- PC running Windows XP / Windows 7
- USB cable to connect the phone to your PC.
You can more info on the project here
You can download the SDK from the Official SMS Server Toolkit Site