fulltext search stemming/ spelling problems

Hi!

I'm using postgres 8.4.3 and try to get stemming/ wrong word correction
working.

I already installed the myspell dictionaries using apt-get and created
postgres dictionaries like this:

Fulltext search configuration »public.english_ispell«
Parser: »pg_catalog.default«
Token | Dictionaries
-----------------+------------------------------------
asciihword | english_ispell,english_stem,simple
asciiword | english_ispell,english_stem,simple
email | simple
file | simple
float | simple
host | simple
hword | english_ispell,english_stem,simple
hword_asciipart | english_ispell,english_stem,simple
hword_numpart | simple
hword_part | english_ispell,english_stem,simple
int | simple
numhword | simple
numword | simple
sfloat | simple
uint | simple
url | simple
url_path | simple
version | simple
word | english_ispell,english_stem,simple

But when I do, for example, SELECT to_tsvector('english_ispell',
'gitar') the result is only:
'gitar':1

Shouldn't the word be corrected to 'guitar'?

SELECT plainto_tsquery('english_ispell','gitar') doesn't work neither:
'gitar'

Thanks,
Corin