One of our internal flash devices is mounted several times

Issue

On one of our systems, there is one internal flash which is showed as a several devices on df and mount:

$ df
/dev/sda1                99091     73176     20799  78% /boot
/dev/sde1                99091     73176     20799  78% /boot
/dev/sdf1                99091     73176     20799  78% /boot

$ mount
/dev/sda1 on /boot type ext3 (rw,noatime,nodiratime,acl,user_xattr)
/dev/sde1 on /boot type ext3 (rw,noatime,nodiratime,acl,user_xattr)
/dev/sdf1 on /boot type ext3 (rw,noatime,nodiratime,acl,user_xattr)

$ lsscsi
[1:0:0:0]    cd/dvd  Optiarc  CDRWDVD CRX890A  PX03  /dev/sr0 
[3:0:0:0]    disk    FUJITSU  MBB2147RC        0105  /dev/sdb 
[3:0:1:0]    disk    FUJITSU  MBB2147RC        0105  /dev/sdc 
[3:0:2:0]    disk    FUJITSU  MBB2147RC        0105  /dev/sdd 
[5:0:0:0]    disk    SMART    eUSB             874D  /dev/sdf