Is this a gmirror bug?

[Wojciech Puchar]

>> Filesystem          1K-blocks      Used     Avail Capacity  Mounted on
>> /dev/mirror/gm0d      4058062   -377792   4111210   110%    /tmp
>> /dev/mirror/gm0e     15231278   -113942  14126718   101%    /var
>>
>> then? I always assumed that a disk occupation > 100% would go into
>> this reserved area, which would turn the Capacity field to be more
>> than 100%, and not less than 0%? This is the case when I have more
>> data on a UFS partition than it "is allowed to"...
>
> I've seen this before a few times, but never something less than 0%.
> I've reimaged the system to correct it. Will have to see if it happens
> again...

did you checked that partitions with fsck? (fsck_ffs -y)

does it detects errors and fix them?
after fsck is it ok or still nonsense in Used?