pgplsh on postgresql 8.0.2

Hi,
I migrated my db from postgresql 7.4.6 to 8.0.2 but I'm not able to make plsh
functions working.
I installed plsh ver. 1.0-7.3 after having installed postgresql 8.0.2 rpms for
fedora core 2.
I used the same, succesfull, install procedure I used on postgresql 7.4.6.

Every time I try to run a plsh function (ie. postmasterstarttime()) I get the
following error message:

sano_gis=# select postmasterstarttime();
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Succeeded.
sano_gis=#

Do you know if plsh ver. 1.0-7.3 is compatible with postgresql 8.0.2 ?
Is there any solution or alternative?

Thank you very much,
Paolo Mattioli