BUG #5487: dblink failed with 63 bytes connection names

The following bug has been logged online:

Bug reference:      5487
Logged by:          Takahiro Itagaki
Email address:      itagaki.takahiro@oss.ntt.co.jp
PostgreSQL version: 9.0beta1
Operating system:   Linux
Description:        dblink failed with 63 bytes connection names
Details:

Contib/dblink module seems to have a bug in handling
connection names in NAMEDATALEN-1 bytes.

It cannot use exiting connections with 63 bytes name
in some cases. For example, we cannot disconnect
such connections. Also, we can reconnect with the
same name and will have two connections with the name.

=# SELECT dblink_connect(repeat('1234567890', 6) || 'ABC',
'host=localhost');
 dblink_connect
----------------
 OK
(1 row)

=# SELECT dblink_get_connections();
                      dblink_get_connections
-------------------------------------------------------------------
 {123456789012345678901234567890123456789012345678901234567890ABC}
(1 row)

=# SELECT dblink_disconnect(repeat('1234567890', 6) || 'ABC');
ERROR:  connection
"123456789012345678901234567890123456789012345678901234567890ABC" not
available