sysinstall partition editor displays funny subtypes

Hi. I notice that the FDISK Partition Editor in sysinstall displays rather 
strange values for the partition types. For example, on a running 
-CURRENT (cvsupped last friday):

Offset       Size(ST)        End     Name  PType       Desc  Subtype 
Flags

          0         63         62        -     12     unused        0
         63   78124032   78124094    ad0s1      4    unknown        0
   78124095        905   78124999        -     12     unused        0

On my home machine a fresh install displayed the ad0s1 as "XENIX /usr" 
(subtype 3). What? :)

I notice that fdisk displays the partition type ok.

Here is the output from 'sysctl -b kern.geom.conftxt'

0 DISK ad0 40000000000 512 hd 16 sc 63
1 MBR ad0s1 39999504384 512 i 0 o 32256
2 BSD ad0s1f 38141648896 512 i 5 o 1857855488
2 BSD ad0s1e 268435456 512 i 4 o 1589420032
2 BSD ad0s1d 268435456 512 i 3 o 1320984576
2 BSD ad0s1c 39999504384 512 i 2 o 0
2 BSD ad0s1b 1052549120 512 i 1 o 268435456
2 BSD ad0s1a 268435456 512 i 0 o 0

Shouldn't there be a 'ty' entry for the MBR so that libdisk can populate 
the subtype member properly?

Cheers
Michiel