Insert Assertion Failed in strcoll_l.c:112

Hi,

The following is written to /var/log/postgresql/postgresql-9.1-main.log:

127.0.0.1(59800) INSERT: strcoll_l.c:112: __strcoll_l: Assertion
`((uintptr_t)
indirect) % __alignof__ (indirect[0]) == 0' failed.
2012-12-23 08:54:54 SGT LOG: server process (PID 1964) was terminated by
signal
6: Aborted
2012-12-23 08:54:54 SGT LOG: terminating any other active server processes
2012-12-23 08:54:54 SGT WARNING: terminating connection because of crash
of ano
ther server process
2012-12-23 08:54:54 SGT DETAIL: The postmaster has commanded this server
proces
s to roll back the current transaction and exit, because another server
process
exited abnormally and possibly corrupted shared memory.
2012-12-23 08:54:54 SGT HINT: In a moment you should be able to reconnect
to th
e database and repeat your command.

Error occurring on Ubuntu 12.04 with PostgreSQL 9.1 on Dell PowerEdge R710

Same code executes successfully on Ubuntu 12.10 with PostgreSQL 9.1 on Dell
Precision 390.

Application is a libpq c-application. Application is inserting a large
number of records into the DB, for later query. Uses a thread pool and
connection pool. Connection pool establishes connections up-front and
hands them to threads when required. Connection pools creates 5 prepared
statements to assist with the inserts on each connection. 70 Connections
in the connection pool, up to 150 threads in the thread pool. Mutex's
manage contention on the connection pool. Application successfully inserts
100+ records in the first table and 1000+ records in the second table
before failing. After the above error all connections begin to report 'no
connection' to the database.

Configuration in /etc/postgresql/9.1/main/postgresql.conf is as follows:
fysnc =on
full_page_writes = on
max_connections = 150
max_prepared_transactions = 350
max_locks_per_transaction = 10

Configuration in /etc/sysctl.conf :
kernel.shmmax=131072000

Feels like a configuration issue. Any suggestions on where to start
looking would be appreciated.

Kind regards,
Michael