"It is why I asked to to look inside .hex file!"

Thanks Oleg.

You have a defined a case where a program like FLIP does not bother to fill in unused code address.

But in my case there are no empty code address spaces. It is just that when I try to fill in 0x00, for some funny reason FlashMagic fills them with 0xff. OK I am currently stuck in a site and hopefully resolve this when I get back - as I know that this is what is happening.

Raghu