Description of problem:
I've got a crash on libais_disconnect_request() on a restart of corosync. The conn_info->conn_info_partner are NULL.

------- Here is the backtrace :
Core was generated by `corosync'.
Program terminated with signal 11, Segmentation fault.
Reading symbols from /lib/libthr.so.3...done.
Loaded symbols for /lib/libthr.so.3
Reading symbols from /lib/libc.so.7...done.
Loaded symbols for /lib/libc.so.7
Reading symbols from /usr/libexec/lcrso/objdb.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/objdb.lcrso
Reading symbols from /usr/libexec/lcrso/openaisserviceenable.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/openaisserviceenable.lcrso
Reading symbols from /usr/libexec/lcrso/openaisparser.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/openaisparser.lcrso
Reading symbols from /usr/libexec/lcrso/service_clm.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/service_clm.lcrso
Reading symbols from /usr/libexec/lcrso/service_ckpt.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/service_ckpt.lcrso
Reading symbols from /usr/libexec/lcrso/service_lck.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/service_lck.lcrso
Reading symbols from /usr/libexec/lcrso/service_evs.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/service_evs.lcrso
Reading symbols from /usr/libexec/lcrso/service_cfg.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/service_cfg.lcrso
Reading symbols from /usr/libexec/lcrso/service_cpg.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/service_cpg.lcrso
Reading symbols from /usr/libexec/lcrso/service_confdb.lcrso...done.
Loaded symbols for /usr/libexec/lcrso/service_confdb.lcrso
Reading symbols from /libexec/ld-elf.so.1...done.
Loaded symbols for /libexec/ld-elf.so.1
#0  0x08051a4d in libais_disconnect_request (conn_info=0x821a110) at ipc.c:406
406     ipc.c: No such file or directory.
        in ipc.c
[New Thread 0x8203200 (LWP 100092)]
(... snip ...)
[New Thread 0x8201100 (LWP 100064)]
(gdb) p conn_info
$1 = (struct conn_info *) 0x821a110
(gdb) p *conn_info
$2 = {
  fd = 12, 
  events = 37, 
  state = CONN_STATE_REQUESTED, 
  thread = 0x8201500, 
  thread_attr = 0x820aac0, 
  inb = 0x8300000 "\030", 
  inb_nextheader = 0, 
  inb_start = 0, 
  inb_inuse = 0, 
  outq = {
    head = 1, 
    tail = 799, 
    used = 1, 
    usedhw = 1, 
    size = 800, 
    items = 0x8218000, 
    size_per_item = 8, 
    iterator = 0, 
    mutex = 0x8205900
  }, 
  byte_start = 0, 
  service = CPG_SERVICE, 
  authenticated = 1, 
  private_data = 0x0, 
  conn_info_partner = 0x0, <<<<<<<<<<<<<<<<<<<<
  flow_control_handle = 0, 
  flow_control_enabled = 0, 
  flow_control_local_count = 0, 
  flow_control = 0, 
  flow_control_mutex = 0x8205a40, 
  lib_exit_fn = 0, 
  timerlist = {
    timer_head = {
      next = 0x0, 
      prev = 0x0
    }, 
    timer_iter = 0x0
  }, 
  mutex = 0x8205940, 
  shared_mutex = 0x8216150, 
  list = {
    next = 0x821a198, 
    prev = 0x821a198
  }
}
(gdb) 

--------- Here is the actual code
 402 static void libais_disconnect_request (struct conn_info *conn_info)
 403 {
 404     if (conn_info->state == CONN_STATE_ACTIVE) {
 405         conn_info->state = CONN_STATE_REQUESTED;
 406         conn_info->conn_info_partner->state = CONN_STATE_REQUESTED; <<<<<
 407     }

Version-Release number of selected component (if applicable):
corosync-trunk, rev 1667

How reproducible:
Random crash, don't known >_<