Mainline 2.6.30.1 always stuck at "done, booting the kernel"

I've been trying to get this kernel (from cbxbiker) to boot for several days now, and no matter what I try, it always gets stuck with the message "Uncompressing Linux...done, booting the kernel", at which point I have no choice but to insert a pin into the reset hole. I've tried booting it from SD card and via TFTP with the same results. I have no trouble booting the stock kernel (2.6.22.18) from NAND, SD, or TFTP, and I'm using the modified uBoot created by kwonsk a few months ago (described here: http://plugcomputer.org/plugforum/index.php?topic=183.30).

I've been searching the forums, but I'm not exactly a Linux guy, so some of the stuff mentioned doesn't make a lot of sense to me. But from what I've gathered, is it possible that:

1) Since the newer kernel is somewhat larger than the stock kernel, by about 600,000 bytes, do I need an even newer version of uBoot? Do I need to adjust the orion_nand parameters somehow?
2) I'm using a high-speed (SanDisk Extreme III 4 GB) SD card, and while I haven't had any problems with it, I do keep finding posts about disabling high-speed operations in the kernel. I'm able to get to the exact same point when I boot the kernel via TFTP, but is this high-speed card somehow the problem?

I would really appreciate any help anyone can give in this area. Thanks in advance.

Working config; stock kernel and rootfs on SD card:

Code:

bootsd=mmcinit;ext2load mmc 0:1 0x2000000 /$(image_name)
bootargs_sd=root=/dev/mmcblk0p1 rw
console=console=ttyS0,115200 mtdparts=nand_mtd:0x100000@0(uboot)ro,0x0@0x100000(uImage),0x1ff00000@0x100000(rootfs)rw
boot_sd=set mainlineLinux no; run bootsd; setenv bootargs $(console) $(bootargs_sd) ip=$(ipaddr):$(serverip)$(bootargs_end);bootm 0x2000000
image_name=uImage.sheeva.040309

Non-working config; mainline 2.6.30.1 kernel and rootfs on SD card:

Code:

boot_sd_mainline=setenv image_name sheeva-2.6.30.1-uImage;setenv mainlineLinux yes;run bootsd;setenv bootargs $(bootargs_mainline);bootm 0x2000000
bootargs_mainline=console=ttyS0,115200 mtdparts=orion_nand:0x400000@0x100000(uImage),0x1fb00000@0x500000(rootfs) rw root=/dev/mmcblk0p1 rw ip=192.168.1.119:192.168.1.21:::DB88FXX81:eth0:none
arcNumber=2097

Non-working config; mainline 2.6.30.1 kernel on TFTP and rootfs on SD card:

Code:

boot_nfs_mainline=setenv image_name sheeva-2.6.30.1-uImage;setenv mainlineLinux yes;run boottftp;setenv bootargs $(bootargs_mainline);bootm 0x2000000
boottftp=tftpboot 0x2000000 $(image_name)
bootargs_mainline=console=ttyS0,115200 mtdparts=orion_nand:0x400000@0x100000(uImage),0x1fb00000@0x500000(rootfs) rw root=/dev/mmcblk0p1 rw ip=192.168.1.119:192.168.1.21:::DB88FXX81:eth0:none
arcNumber=2097

Full dump:

Code:

CASset=min
MALLOC_len=1
arcNumber=2097
autoload=no
baudrate=115200
boot_nand=run bootnand;setenv bootargs $(console) $(bootargs_nand) ip=$(ipaddr):$(serverip)$(bootargs_end);bootm 0x2000000
boot_nfs=run boottftp;setenv bootargs $(console) $(bootargs_nfs) nfsroot=$(serverip):$(rootpath) ip=$(ipaddr):$(serverip)$(bootargs_end);bootm 0x2000000
boot_nfs_mainline=setenv image_name sheeva-2.6.30.1-uImage;setenv mainlineLinux yes;run boottftp;setenv bootargs $(bootargs_mainline);bootm 0x2000000
boot_sd=set mainlineLinux no; run bootsd; setenv bootargs $(console) $(bootargs_sd) ip=$(ipaddr):$(serverip)$(bootargs_end);bootm 0x2000000
boot_sd_mainline=setenv image_name sheeva-2.6.30.1-uImage;setenv mainlineLinux yes;run bootsd;setenv bootargs $(bootargs_mainline);bootm 0x2000000
bootargs=console=ttyS0,115200 mtdparts=nand_mtd:0x100000@0(uboot)ro,0x0@0x100000(uImage),0x1ff00000@0x100000(rootfs)rw root=/dev/mtdblock2 rw ip=192.168.1.119:192.168.1.21:::DB88FXX81:eth0:none
bootargs_end=:::DB88FXX81:eth0:none
bootargs_mainline=console=ttyS0,115200 mtdparts=orion_nand:0x400000@0x100000(uImage),0x1fb00000@0x500000(rootfs) rw root=/dev/mmcblk0p1 rw ip=192.168.1.119:192.168.1.21:::DB88FXX81:eth0:none
bootargs_nand=root=/dev/mtdblock2 rw
bootargs_nfs=root=/dev/nfs rw
bootargs_root=root=/dev/nfs rw
bootargs_sd=root=/dev/mmcblk0p1 rw
bootcmd=run boot_sd
bootdelay=3
bootnand=nand read.e 0x2000000 0x00100000 0x00500000
bootsd=mmcinit;ext2load mmc 0:1 0x2000000 /$(image_name)
boottftp=tftpboot 0x2000000 $(image_name)
cesvcid=ULULULULULULPPULULULULULDA
console=console=ttyS0,115200 mtdparts=nand_mtd:0x100000@0(uboot)ro,0x0@0x100000(uImage),0x1ff00000@0x100000(rootfs)rw
console_mainline=console=ttyS0,115200 mtdparts=orion_nand:0x400000@0x100000(uImage),0x1fb00000@0x500000(rootfs) rw
disL2Cache=no
disL2Prefetch=yes
disaMvPnp=no
enaAutoRecovery=yes
enaCpuStream=no
enaDCPref=yes
enaICPref=yes
enaMonExt=no
enaWrAllo=no
ethact=egiga0
ethaddr=00:50:43:01:C4:BD
ethmtu=1500
ethprime=egiga0
fileaddr=2000000
filesize=1F972C
image_name=uImage.sheeva.040309
ipaddr=192.168.1.119
loadaddr=0x02000000
loads_echo=0
mainlineLinux=no
mvNetConfig=mv_net_config=(00:11:88:0f:62:81,0:1:2:3),mtu=1500
mvPhoneConfig=mv_phone_config=dev0:fxs,dev1:fxs
nandEcc=1bit
netbsd_en=no
netmask=255.255.0.0
netretry=no
pexMode=RC
rcvrip=169.254.100.100
rootpath=/root/rootfsv1.0
run_diag=no
sata_dma_mode=yes
serverip=192.168.1.21
setL2CacheWT=yes
standalone=fsload 0x2000000 $(image_name);setenv bootargs $(console) root=/dev/mtdblock0 rw ip=$(ipaddr):$(serverip)$(bootargs_end) $(mvPhoneConfig); bootm 0x2000000;
stderr=serial
stdin=serial
stdout=serial
usb0Mode=host
vxworks_en=no
yuk_ethaddr=00:00:00:EE:51:81