Hi Friends,
Here I am again Puting accross point where I thought for second.
The solution for registering mediator for component in popup created at run time is below.
reportPopup = PopUpManager.createPopUp(this.payrollModule,PdfReportFrame,true) as PdfReportFrame;
registerMediator(new PdfReportFrameMediator(reportPopup)); //this without resolving component on parent
PopUpManager.centerPopUp(reportPopup);
Every thing else goes same way.
Ranjit