Select slow over network

Hello. I'm using PostgreSQL 8.1.4 with WinXP Sp2.
The acess over network 100mbit is too slow.
My query take 100 times more.
The use of CPU and network is low, less than 1%.
Searching in the web I found other with the same problem, but no reply to
resolve this problem.
The query is a simple "SELECT * FROM table".
the EXPLAIN of the query:
Seq Scan on cliente_geral (cost=0.00..344.95 rows=6795 width=587)

Thanks.