Laravel queue listener with supervisord results in core dump

I'm using Laravel 4 and its queue implementation for some asynchronous tasks, and I want to use supervisord to manage the worker processes (basically artisan queue:listen), like I've done in the past with other frameworks.

When I run supervisord manually, it starts up the worker processes just fine, but when I run it as a service, the worker processes die immediately with this message:

2013-07-25 09:51:32,162 INFO spawned: 'myproject' with pid 4106
2013-07-25 09:51:32,875 INFO exited: myproject (terminated by SIGSEGV (core dumped); not expected)

There's no stdout or stderr output.

Here's the supervisord configuration for the workers (nothing fancy):

[program:myproject]
command=php artisan queue:listen --queue=queue_name iron --env=staging
directory=/home/myuser/myproject
stdout_logfile=/var/log/supervisord/myproject.stdout
stderr_logfile=/var/log/supervisord/myproject.stderr

The server its running on is a CentOS 6.4 64 bit with PHP 5.3.25 from cPanel/WHM (not my choice, it's a server that was idle and about which we can't do much).

Any ideas on what could be causing the problem?

from Laravel queue listener with supervisord results in core dump