Weird init script issue with corosync

This probably has a simple explanation, but I certainly can't think of it.

I've got corosync installed (via yum), with it's default init script. Something is strange on this particular CentOS installation as I often need to manually link /etc/rc.d/init.d/ to /etc/init.d.

The issue is that it fails when run via it's symbolic link, yet it runs fine through /etc/rc.d/init.d

What's even weirder is it fails to run if run using the full path, and only if actually run in the /etc/rc.d/init.d directory.

Example:

[~]# /etc/rc.d/init.d/corosync start
     Starting Corosync Cluster Engine (corosync):               [FAILED]
[~]# service corosync status
     corosync is stopped
[~]# cd /etc/rc.d/init.d/
[init.d]# /etc/rc.d/init.d/corosync start
          Starting Corosync Cluster Engine (corosync):          [FAILED]
[init.d]# corosync start
[init.d]# service corosync status
          corosync (pid  1985) is running...

Any explanation?

Edit:

Not sure what I've changed exactly, but it now works when started from /rc.d/init.d, but not with service corosync start.

[root@server2 mirror]# /etc/rc.d/init.d/corosync start
Starting Corosync Cluster Engine (corosync):               [  OK  ]

[root@server2 mirror]# /etc/init.d/corosync start
Starting Corosync Cluster Engine (corosync):               [FAILED]

[root@server2 mirror]# service corosync start
Starting Corosync Cluster Engine (corosync):               [FAILED]

edit 2:

Made a symbolic link from /etc/rc.d/init.d to /etc/init.d .. and now it works when run via service corosync start.. yet doesn't start on boot, argh.

Edit 3:

It's working with every command except on boot.

I've changed the run level to 99, which it still fails on, and I've changed the path inside the script to the absolute path : /usr/sbin/corosync

I've also done diffs of the environmental variables:

On service corosync start:

_=/bin/env
LANG=en_US.UTF-8
PATH=/sbin:/usr/sbin:/bin:/usr/bin
PWD=/
SHLVL=1
TERM=xterm

On boot:

_=/bin/env
LANG=en_US.UTF-8
PATH=/sbin:/usr/sbin:/bin:/usr/bin
PWD=/
SHLVL=2
TERM=linux
CONSOLETYPE=vt
LANGSH_SOURCED=1
previous=N
PREVLEVEL=N
runlevel=3
RUNLEVEL=3
UPSTART_EVENTS=runlevel
UPSTART_INSTANCE=
UPSTART_JOB=rc

Boot log:

Starting Corosync Cluster Engine (corosync):    [FAILED]