I'm having the same problems w/ kickstart. it seems only to happen when try to remove packages (-<packagename>). i can get kickstart to work if i include groups (@<groupname>), but not if i try to remove individual packages.
i even tried to use the kickstart file that was generated during an install, that failed. so here's my ks.cfg:
------------------------------------------------------
lang en_US
langsupport --default=en_US
keyboard us
mouse
timezone America/New_York
rootpw --iscrypted ******************
text
install
url --url
http://<servername>/fc4-i386/disc1
bootloader --location=mbr
zerombr yes
clearpart --all --initlabel
part /boot --fstype ext3 --size=100
part pv.2 --size=0 --grow
volgroup VolGroup00 --pesize=32768 pv.2
logvol / --fstype ext3 --name=LogVol00 --vgname=VolGroup00 --size=1024 --grow
logvol swap --fstype swap --name=LogVol01 --vgname=VolGroup00 --size=128 --grow --maxsize=256
auth --useshadow --enablemd5
network --bootproto=static --ip=<ipaddress> --netmask=255.255.255.0 --gateway=<gateway> --nameserver=<dns> --device=eth0
firewall --disabled
selinux --disabled
skipx
%packages
@ mysql
@ editors
@ system-tools
@ dialup
@ ftp-server
@ java
@ legacy-software-development
@ smb-server
@ web-server
@ printing
@ language-support
@ dns-server
@ development-tools
-mysql-devel
-php-ldap
-perl-LDAP
net-snmp-utils
-gcc-gfortran
-perl-XML-Twig
memtest86+
-bind-chroot
kernel
-perl-XML-NamespaceSupport
grub
kernel-devel
-ctags
-texinfo
-xdelta
-a2ps
-cvs
-perl-XML-Parser
-system-config-samba
-MyODBC
-valgrind
-httpd-manual
-nmap
e2fsprogs
-unixODBC
-perl-XML-LibXML-Common
-cscope
-perl-XML-Encoding
-python-ldap
-tux
-bluez-pin
-squid
-screen
-libdbi-dbd-mysql
-perl-XML-Grove
-openldap-clients
-MySQL-python
lvm2
-perl-XML-SAX
-valgrind-callgrind
-rcs
mrtg
php-mysql
-indent
-perl-XML-LibXML
-open
-perl-XML-Dumper
-byacc
-ckermit
%post