MTD mount problem on Mikrotik RBM11G

Hi, I have Mikrotik RBM11G board. When I try to mount mtd partitions in installation process I get:

root@OpenWrt:/# mount -o ro /dev/mtdblock1 /mnt/kernel/
mount: mounting /dev/mtdblock1 on /mnt/kernel/ failed: Invalid argument

In mtd table I see all partitions but can't mount it.

root@OpenWrt:/# cat /proc/mtd 
dev:    size   erasesize  name
mtd0: 00040000 00010000 "RouterBoot"
mtd1: 0000f000 00010000 "bootloader1"
mtd2: 00001000 00010000 "hard_config"
mtd3: 0000f000 00010000 "bootloader2"
mtd4: 00001000 00010000 "soft_config"
mtd5: 00001000 00010000 "bios"

Can anyone help me?