Size of a kernel module is different at build place and after installation

[sobtwmxt <sobtwmxt@sdf.lonestar.org>]

  I have built a custom kernel, using make-kpgk, from debian source.
Using ls -l, there is difference in the size of kernel modules, .ko 
files, at build place and after installation of the package.  I 
only looked at 2 unrelated modules, but I think there will be a
difference in the size of other modules too.  If that matters, I built 
the package on one machine, and installed it on another.  The later 
machine is an x86 running Ubuntu.  The former is x86 running Debian.
  
1) Why there is size difference?
2) Can I compile modules on the Debian machine and copy the resulted 
   .ko files directly to the Ubuntu machine?
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sobtwmxt@sdf.lonestar.org
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