fdisk won't save changes

I would much appreciate it if somebody experienced with MTD could point out something I'm doing wrong, direct me toward a solution, or, alternatively, confirm that the mtd drivers are just not up to production use for DOC2000.

Linux kernel 2.4.18
Have built many kernels with all relevant features turned on 188M DOC2000

If I build my kernel with the nftlcore.c v. 1.86, upon bootup I get:

    Jul 15 22:43:39 vox kernel: ftl_cs: FTL header not found.
    Jul 15 22:43:39 vox kernel: NFTL driver: nftlcore.c $Revision: 1.86 
$, nftlm
ount.c $Revision: 1.25 $
    Jul 15 22:43:39 vox kernel: Could not find valid boot record
    Jul 15 22:43:39 vox kernel: Could not mount NFTL device

and /dev/nftla is not usable at all.

If I boot with a kernel with nftlcore v. 1.82, I get:

    Jul 15 23:11:47 vox kernel: ftl_cs: FTL header not found.
    Jul 15 23:11:47 vox kernel: NFTL driver: nftlcore.c $Revision: 1.82 
$, nftlm
ount.c $Revision: 1.25 $
    Jul 15 23:11:47 vox kernel: Cannot calculate an NFTL geometry to 
match size
of 0x3bf60.
    Jul 15 23:11:47 vox kernel: Using C:1023 H:16 S:15 (== 0x3bf10 sects)
    Jul 15 23:11:47 vox kernel:  nftla: unknown partition table

I can then actually run fdisk on /dev/nftla, but when fdisk tries to save my changes, entries like this appear in my sys log:

    Jul 15 23:30:41 vox kernel: Argh! No free blocks found! LastFreeEUN 
= 7679,
FirstEUN = 0
    Jul 15 23:30:41 vox kernel: No Virtual Unit Chains available for 
folding. Fa
iling request
    Jul 15 23:30:41 vox kernel: Argh! No free blocks found! LastFreeEUN 
= 7679,
FirstEUN = 0
    Jul 15 23:30:41 vox kernel: Cannot make free space.
    Jul 15 23:30:41 vox kernel: NFTL_writeblock(): Cannot find block to 
write to
    Jul 15 23:30:41 vox kernel: end_request: I/O error, dev 5d:00 
(unknown), sec
tor 14
    Jul 15 23:30:44 vox kernel:  nftla: nftla1 < nftla5 >
    Jul 15 23:30:44 vox kernel:  nftla: nftla1 < nftla5 >

(An associate of mine has had very similar problems when trying to work with CF-- fdisk will not save changes properly).

Her'es my nftldump /dev/mtd0 output:

NFTL Media Header found at offset 0x00010000:
NumEraseUnits: 9214
FirstPhysicalEUN: 2
Formatted Size: 295796736
UnitSizeFactor: 0xff
Second NFTL Media Header found at offset 0x00018000 Unit 2 is free
Unit 3 is free
EraseMark not present in unit 4: ffff
Unit 4 is free
Unit 5 is free
Unit 6 is free
Unit 7 is free
Unit 8 is free
Unit 9 is free
Unit 10 is free
Unit 11 is free
Unit 12 is in chain 2 and is not a replacement Unit 13 is free
Unit 14 is in chain 3 and is not a replacement Unit 15 is free
...
Unit 5932 is free
Memory fault

Help!