PostgreSQL 8.1.0 catalog corruption

I've been running 8.1.0 on a test box since the FreeBSD port has been
available, and it appears that the catalog has become corrupted.
There's plenty of free space on all volumes, so it hasn't run out of
space or anything.

$ uname -a
FreeBSD shi.mochibot.com 6.0-RELEASE FreeBSD 6.0-RELEASE #2: Mon Nov
7 14:34:52 PST 2005 root(at)shi(dot)mochibot(dot)com:/usr/obj/usr/src/sys/
CUSTOM i386

$ psql mochi
Welcome to psql 8.1.0, the PostgreSQL interactive terminal.

Type: \copyright for distribution terms
\h for help with SQL commands
\? for help with psql commands
\g or terminate with semicolon to execute query
\q to quit

mochi=# drop table ping_1132387200;
ERROR: table "ping_1132387200" does not exist
mochi=# create table ping_1132387200();
ERROR: type "ping_1132387200" already exists

I'm not sure what to do about this..

-bob