I got the repository today and tried building the gem under 1.9.2 since there isn't an official release out yet that includes the encoding fixes for Postgres.
I found that I wasn't able to load rake at all because of a problem finding the rake files under the rake directory. I solved the problem by adding the following to the BEGIN section of the main Rakefile:
$LOAD_PATH.unshift( basedir.to_s ) unless $LOAD_PATH.include?( basedir.to_s )
I think this came up because 1.9.2 removed '.' from the $LOAD_PATH. The same problem also occurred when running the specs and fixed by adding the same to the BEGIN section of spec/m17n_spec.rb. There may be other places it is needed that I don't know of.
Exact version I was using:
ruby 1.9.2dev (2010-01-28 trunk 26458) [x86_64-darwin10.2.0]
Also, just wondering if the spec '- should not read past the end of a large object' is supposed to be failing right now in lo_create. I tried it under 1.8.7-p248 and 1.9.2.