GiST Support in 8.1

We're migrating from a 7.4 (Linux AS2.1) system to an 8.1.5 (Linux RHEL4
X64) system.

In 7.4, we used tsearch (txtidx fields) on some tables.

When we attempt to load the indexes for those fields in 8.1.5, we get a
strange SEGV.

\d historyticket
[cut]
  short_summary_idx | txtidx                      |
[cut]

XXXXX=> CREATE INDEX historyticket_idx_12 ON historyticket USING gist
(short_summary_idx);
server closed the connection unexpectedly
         This probably means the server terminated abnormally
         before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.
!>

 From the server log:

LOG:  statement: CREATE INDEX historyticket_idx_12 ON historyticket
USING gist (short_summary_idx);
LOG:  server process (PID 813) was terminated by signal 11
LOG:  terminating any other active server processes
LOG:  connection received: host=[local]
FATAL:  the database system is in recovery mode
LOG:  all server processes terminated; reinitializing
LOG:  database system was interrupted at 2007-07-24 14:20:17 EDT
LOG:  checkpoint record is at 6/65BCD58
LOG:  redo record is at 6/65BCD58; undo record is at 0/0; shutdown TRUE
LOG:  next transaction ID: 46991; next OID: 161629
LOG:  next MultiXactId: 1; next MultiXactOffset: 0
LOG:  database system was not properly shut down; automatic recovery in
progress
LOG:  redo starts at 6/65BCDA8
LOG:  unexpected pageaddr 5/FD5D4000 in log file 6, segment 6, offset
6111232
LOG:  redo done at 6/65D3F40
LOG:  database system is ready
LOG:  transaction ID wrap limit is 1073785792, limited by database "XXXXXX"


Anyone else run into this problem?  Unfortunately, I didn't set up
tsearch on the 7.4 system, so perhaps I've missed something obvious.