multipath device is still created despite it's being blacklisted

Issue

• The /etc/multipath.conf configuration file blacklists all wwids and has blacklist exceptions for the wwids that are required:

defaults {
        user_friendly_names yes
}
blacklist {
        wwid *
}
blacklist_exceptions {
        wwid 3600c0ff000dae5b8bcf0725001000000
        wwid 3600c0ff0001474afa6f0725001000000
}

This correctly results in the following two multipaths :

mpathg (3600c0ff000dae5b8bcf0725001000000) dm-1 HP,P2000 G3 FC
size=4.9T features='1 queue_if_no_path' hwhandler='0' wp=rw
|-+- policy='round-robin 0' prio=50 status=active
| `- 4:0:0:1 sdd 8:48 active ready running
`-+- policy='round-robin 0' prio=10 status=enabled
  `- 3:0:0:1 sdb 8:16 active ready running

mpathf (3600c0ff0001474afa6f0725001000000) dm-0 HP,P2000 G3 FC
size=12T features='1 queue_if_no_path' hwhandler='0' wp=rw
|-+- policy='round-robin 0' prio=50 status=active
| `- 3:0:0:0 sda 8:0  active ready running
`-+- policy='round-robin 0' prio=10 status=enabled
  `- 4:0:0:0 sdc 8:32 active ready running

However, a multipath device is also created for mpatha with wwid 3600508b1001c897367bee13b2580b778 even though it should be black listed :

mpatha (3600508b1001c897367bee13b2580b778) dm-2 HP,LOGICAL VOLUME
size=137G features='0' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=1 status=active
  `- 5:0:0:0 sde 8:64 active ready running

• Getting below error while mounting cciss device

mount: /dev/cciss/c0d1p1 already mounted or /backup busy

If run the dmsetup remove command to remove multipath device (mpath3p1, mpath3) and run a mount -a command and the mount works then.