TSearch2 / German compound words / UTF-8

Hi,

I'm on PG 8.0.4, initDB and locale set to de_DE.UTF-8, FreeBSD.

My TSearch config is based on "Tsearch2 and Unicode/UTF-8" by Markus
Wollny (http://tinyurl.com/a6po4)

The following files are used:

http://hannes.imos.net/german.med [UTF-8]
http://hannes.imos.net/german.aff [ANSI]
http://hannes.imos.net/german.stop [UTF-8]
http://hannes.imos.net/german.stop.ispell [UTF-8]

german.med is from "ispell-german-compound.tar.gz", available on the
TSearch2 site, recoded to UTF-8.

The first problem is with german compound words and does not have to do
anything with UTF-8:

In german often an "s" is used to "link" two words into an compound
word. This is true for many german compound words. TSearch/ispell is not
able to break those words up, only exact matches work.

An example with "Produktionsintervall" (production interval):

fts=# SELECT ts_debug('Produktionsintervall');
ts_debug
--------------------------------------------------------------------------------------------------
(default_german,lword,"Latin
word",Produktionsintervall,"{de_ispell,de}",'produktionsintervall')

Tsearch/isepll is not able to break this word into parts, because of the
"s" in "Produktion/s/intervall". Misspelling the word as
"Produktionintervall" fixes it:

fts=# SELECT ts_debug('Produktionintervall');
ts_debug
---------------------------------------------------------------------------------------------------------------------
(default_german,lword,"Latin
word",Produktionintervall,"{de_ispell,de}","'ion' 'produkt' 'intervall'
'produktion'")

How can I fix this / get TSearch to remove/stem the last "s" on a word
before (re-)searching the dict? Can I modify my dict or hack something
else? This is a bit of a show stopper :/

The second thing is with UTF-8:

I know there is no, or no full support yet, but I need to get it as good
as it's possible /now/. Is there anything in CVS that I might be able to
backport to my version or other tips? My setup works, as for the dict
and the stop word files, but I fear the stemming and mapping of umlauts
and other special chars does not as it should. I tried recoding the
german.aff to UTF-8 as well, but that breaks it with an regex error
sometimes:

fts=# SELECT ts_debug('dass');
ERROR: Regex error in '[^sãŸ]$': brackets [] not balanced
CONTEXT: SQL function "ts_debug" statement 1

This seems while it tries to map ss to ß, but anyway, I fear, I didn't
anything good with that.

As suggested in the "Tsearch2 and Unicode/UTF-8" article I have a second
snowball dict. The first lines of the stem.h I used start with:

> extern struct SN_env * german_ISO_8859_1_create_env(void);

So I guess this will not work exactly well with UTF-8 ;p Is there any
other stem.h I could use? Google hasn't returned much for me :/

Thanks for reading and all our time. I'll consider the donate button
after I get this working ;/

--
Regards,
Hannes Dorbath