2003 sp1 volumed license ignores autopartition = 1 on unattended

I have a build system that boots from dos. If I do an unattended install
using the standard windows server 2003 it installs with no problems. If I
use the exact same unattended file and install either a slipstreamed 2003 SP1
or a volumed licensed 2003 sp1 it stops at partitioning. What can I do to
prevent this from happening?

%source%\winnt /s:%source% /t:%drive% /u:C:\UNATTEND.TXT

[Data]
AutoPartition=1
MsDosInitiated="1"
UnattnededInstall="Yes"

[Unattended]
UnattendMode = FullUnattended
ExtendOemPartition = 1
FileSystem = ConvertNTFS
DriverSigningPolicy = Ignore
OemPnPDrviersPath = "Compaq\Modem;Drivers\NIC"
OemPreinstall = yes
OemSkipEula = yes
Repartition = no
TargetPath = \Windows

[GuiUnattended]
AdminPassword = *
AutoLogon = Yes
AutoLogonCount = 10
OemSkipRegional=1
OemSkipWelcome=1
TimeZone = 20

.....other sections left out for brevity.