Scheduled Task Error

We have a requirement to implement a custom Scheduled Task. I have implemented the extension. However, on execution, we are getting this error:

ERROR [PSTaskAdapter] Failed to execute job: id=0-36-301, label=New
sFeed
com.percussion.extension.PSExtensionException: The Java handler could not initia
lize the manvinder_ScheduledExt extension: java.lang.InstantiationException.
at com.percussion.extension.PSJavaExtensionHandler.loadExtension(Unknown
Source)
at com.percussion.extension.PSExtensionHandler.prepare(Unknown Source)
at com.percussion.extension.PSExtensionManager.prepareExtension(Unknown
Source)
at com.percussion.services.schedule.impl.PSTaskAdapter.╘00000(Unknown So
urce)
at com.percussion.services.schedule.impl.PSTaskAdapter.o00000(Unknown So
urce)
at com.percussion.services.schedule.impl.PSTaskAdapter.runJob(Unknown So
urce)
at com.percussion.services.schedule.impl.PSSchedulingService$_b.run(Unkn
own Source)

As per the specs, our extension does implements IPSTask interface, and i have registered it in the Extensions.xml.
This error is coming when we go to Admin and try to run this task manually.

Is there anything else we need to do to make it work?