subvertion treat PostScript files as binary?

[Anton Shterenlikht]

Why does subversion treats PostScript files as binary?
I changed the bounding box in a text editor, but can't
use svn diff:

TZAV> svn diff rep-room-mises-mesh.ps
Index: rep-room-mises-mesh.ps
===================================================================
Cannot display: file marked as a binary type.
svn:mime-type = application/postscript

Is there an option somewhere to let svn know
that these are just plain text?

Thanks

Anton