Recompiling a package

["Nelson A. de Oliveira" <n3150nao@bol.com.br>]

Hi people

I was searching for a package and I've found it. But it´s compiled for 
Debian stable. I use Debian unstable and I would like to compile it for 
my version of Debian.
How can I recompile it? I have those files:
program.diff.gz
program.dsc
program.changes
program.deb
program.orig.tar.gz

I know how to create Debian packages, but only to create new packages.
Unpacking the .orig.tar.gz only creates the directory of the program, 
but without the debian/ directory. What do I have to do?

Thank you very much

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