Lingua::Wordnet and base forms

[alexxx...@gmail.com]

Hi people,

I started using the module Lingua::Wordnet since a little time - it
allowed me to interface to Wordnet in a simple way...

Since some days I noticed something strange, which I guess is related
to the base form of a word:

print($wn->lookup_synset("strikes",'n')) returns nothing, while:
print($wn->lookup_synset("strike",'n')) returns:
strike, work stoppage -- (a group's refusal to work in protest against
low pay or bad work conditions; "the strike lasted more than a month
before it was settled" )strike -- (an attack that is intended to seize
or inflict damage on or destroy an objective; "the strike was scheduled
to begin at dawn" )strike -- ((baseball) a pitch that the batter
swings at and misses, or that the batter hits into foul territory, or
that the batter does not swing at but the umpire judges to be in the
area over home plate and between the batter's knees and shoulders;
"this pitcher throws more strikes than balls" )rap, strike, tap -- (a
gentle blow )strike, ten-strike -- (a score in tenpins: knocking down
all ten with the first ball; "he finished with three strikes in the
tenth frame" )hit, smash, smasher, strike, bang -- (a conspicuous
success; "that song was his first hit and marked the beginning of his
career"; "that new Broadway show is a real smasher"; "the party went
with a bang" )

believing that the problem could be related to $wn->morph I used it
directly, and I noticed that it returns always empty!

Any guess??

thank you,

Alessandro Magni

P.S. setup: WordNet-2.1, Lingua-Wordnet-0.74 on Linux FC5