When I try to start the correlator in daemon mode, specifying the pid file, it doesn't start (the pid file exists and is writable by the user).

$ /usr/bin/prelude-correlator -d -P /var/run/prelude-correlator.pid
$ ps axf |grep prelude-correlator |wc -l
0

Strace shows something weird in the code:

$ strace -s 256 -f /usr/bin/prelude-correlator -d -P /var/run/prelude-correlator.pid
[...]
[pid 12080] write(2, "  File \"/usr/lib/pymodules/python2.5/PreludeCorrelator/main.py\", line 147, in main\n", 83) = 83
[...]
[pid 12080] write(2, "    ", 4)         = 4
[pid 12080] write(2, "open(pidfile, \"w\").write(str(os.getpid()))\n", 43) = 43
[pid 12080] close(3)                    = 0
[pid 12080] munmap(0x7f1c86a02000, 4096) = 0
[pid 12080] write(2, "NameError", 9)    = 9
[pid 12080] write(2, ": ", 2)           = 2
[pid 12080] write(2, "global name 'pidfile' is not defined", 36) = 36

PS: logging the output to syslog would be a nice feature