This is due to the name being incorrectly entered in the Tax dept. database. I faced the same issue and here's what i did,
Go to the following url https://onlineservices.tin.nsdl.com/etaxnew/tdsnontds.jsp
This is the site to make online payment to the tax dept.
Select 'Challan No. /ITNS 280'
Enter your PAN and other mandatory details and click 'Proceed'.
The screen that comes next will ask you to verify if the name corresponds to the PAN no.
Here's where you will see some discrepancy that the tax dept. database has regarding your name.
For now - Use the name specified in the screen to register yourself for tax filing. Later you can file an application to the tax dept to correct your name.
Hope this helps.