"kernel stack not valid halt" via bootp

Hi Managers,

 i want to netboot my es40, because it's "local storage" generates too much heat ;]

I boot from SRM (V7.2) via bootp. The alpha gets it IP correctly and downloads the kernel succesfully, but when jumping to the kernel it throws 

"kernel stack not valid halt" 
halt code = 2 
PC = 0

so it goes. All kernels boot fine from local dka, but fail via bootp/tftp. 

What now?!

Thank you,
Armin



For those who care:
boot_dev                ewa0.0.0.2002.1
bootdef_dev             ewa0.0.0.2002.1
booted_dev              ewa0.0.0.2002.1
ewa0_arp_tries          3
ewa0_bootp_file
ewa0_bootp_server
ewa0_bootp_tries        3
ewa0_def_ginetaddr      0.0.0.0
ewa0_def_inetaddr       0.0.0.0
ewa0_def_inetfile
ewa0_def_sinetaddr      0.0.0.0
ewa0_def_subnetmask     0.0.0.0
ewa0_ginetaddr          0.0.0.0
ewa0_inet_init          bootp
ewa0_inetaddr           192.168.7.16
ewa0_inetfile           /vmunix.alpha
ewa0_loop_count         4
ewa0_loop_inc           d0
ewa0_loop_patt          ffffffffffffffff
ewa0_loop_size          100
ewa0_lp_msg_node        6
ewa0_mode               Auto-Negotiate
ewa0_protocols          BOOTP
ewa0_sinetaddr          192.168.7.241
ewa0_tftp_blocksize     1024
ewa0_tftp_tries         3
i                       ewa0.0.0.2002.1


P00>>>boot ewa0
(boot ewa0.0.0.2002.1 -flags A)

Trying BOOTP boot.

Broadcasting BOOTP Request...
Received BOOTP Packet File Name is: /vmunix.alpha
local inet address: 192.168.7.16
remote inet address: 192.168.7.241
TFTP Read File Name: /vmunix.alpha
netmask = 255.255.255.0
Server is on same subnet as client.
................................................................
................................................................
................................................................
...........................
bootstrap code read in
base = 200000, image_start = 0, image_bytes = da5050(14307408)
initializing HWRPB at 2000
initializing page table at 3fb58000
initializing machine state
setting affinity to the primary CPU
jumping to bootstrap code
P00>>>


Filesize on tftp server is correct:
-rwxr-xr-x 1 root root 14307408 Jan 15 12:17 /tftpboot/vmunix.alpha

My bootptap:
.default:\
        :hn:dn="purrcats.de":\
        :td=/tftpboot:\
        :ds=10.0.9.6:\
        :to=auto:


alpha: ht=ether:ip=192.168.7.16:td=/tftpboot:bs=27944:bf=vmunix.alpha:bs=auto:rp=/tmp/foo/:ha=00062b014008