I tried building subversion from a directory _build in the source (rather than building in tree). This worked fine for subversion, but the swig bindings failed because (for example) svn_client.c was not copied to _build/subversion/bindings/swig/python/
Building in tree works fine, but the configure process should probably be modified so that the bindings can also be built out of tree. Michael. P.S. The documentation about how to build the bindings is *extremely* poorly advertised. A search for "python bindings" on the main page should at least turn up something that tells people to read the INSTALL file in the subversion/bindings/swig directory as one of the first links...