Like syedhussain mentioned, first of all, please mention the reasons [from the Company's perspective] why your resignation isn't being accepted. In a way, Praveen Kumar Kambhampati is very right from the Company's point of view.
Career Perspective
Now, looking at this situation from YOUR career perspective, please understand that any/every company likes to hire those who work/stay in the company for a reasonable length of time. Unless you can justify with very strong and valid reasons your leaving the very first company within a year of joining, you will be putting yourself at risk in terms of credibility.
You haven't mentioned whether you resigned AFTER getting another job or want to hunt for another job after resigning—I have seen quite a few IT people quitting even without anything new in hand.
If you can give the picture in detail, you can get the best possible suggestion from this Forum.
Regards, TS