intermittent FD regression check failure

The sort of failure shown below has happened a few times recently. See
recent failures on crake, mastodon and casteroides at
<http://www.pgbuildfarm.org/cgi-bin/show_failures.pl>. It seems harmless
enough. Do we need an alternative regression results file, or is there
some way to prevent this?

cheers

andrew

*** /home/bf/bfr/root/HEAD/pgsql.4238/../pgsql/src/test/regress/expected/foreign_data.out Fri Apr 1 11:37:02 2011
--- /home/bf/bfr/root/HEAD/pgsql.4238/src/test/regress/results/foreign_data.out Mon Apr 25 09:41:48 2011
***************
*** 1088,1098 ****
DROP USER MAPPING FOR regress_test_role SERVER s6;
DROP FOREIGN DATA WRAPPER foo CASCADE;
NOTICE: drop cascades to 5 other objects
! DETAIL: drop cascades to server s4
drop cascades to user mapping for foreign_data_user
drop cascades to server s6
- drop cascades to server s9
- drop cascades to user mapping for unprivileged_role
DROP SERVER s8 CASCADE;
NOTICE: drop cascades to 2 other objects
DETAIL: drop cascades to user mapping for foreign_data_user
--- 1088,1098 ----
DROP USER MAPPING FOR regress_test_role SERVER s6;
DROP FOREIGN DATA WRAPPER foo CASCADE;
NOTICE: drop cascades to 5 other objects
! DETAIL: drop cascades to server s9
! drop cascades to user mapping for unprivileged_role
! drop cascades to server s4
drop cascades to user mapping for foreign_data_user
drop cascades to server s6
DROP SERVER s8 CASCADE;
NOTICE: drop cascades to 2 other objects
DETAIL: drop cascades to user mapping for foreign_data_user