int8 bug on Alpha

Hi,
int8 is not handled correctly on Alpha. Inserting 2^63-1, 2^63-2 and
2^61
into 

create table lint (i int8);

gives

test=# select * from lint;i  
-----1-2 0
(3 rows)

On linux it gives the correct values:

test=# select * from lint;         i          
---------------------922337203685477580792233720368547758062305843009213693952
(3 rows)

This is postgres 7.1b4, compiled with native cc on Tru64 4.0G. I seem to
recall running the regression tests, so perhaps this is not checked?
(just looked at int8.sql, and it is not checked.)

I'm swamped, so cannot look at it right now. If nobody else can look at
it, I will get back to it in about a fortnight.

Adriaan