booting ipxe from pxelinux

[sschneid]

hi everyone,
i reply to this thread because i have a similar problem booting iPXE from pxelinux. I have no access to the dhcp (only to the tftp) and just want to use an existing dhcp group, which comes up with tftp. So i defined

DEFAULT XXXX
LABEL XXXX
KERNEL ipxe/ipxe.lkrn

I compiled ipxe.lkrn with an embedded script for loading a debirf kernel and image. But i don't want to repeat the dhcp request with "ifconf" or "dhcp" command (sometimes it works sometimes not, maybe because of a dhcp loop or whatever, wonder why this worked at all ;-)) With "IPAPPEND 1" in SYSLINUX i could get all the settings (ip, gateway...) from my first request to setting up my net0 manually. But how can i hand over a simple commandline string and post process it in my ipxe script? Or should i compile my own command? Something like

DEFAULT XXXX
LABEL XXXX
KERNEL ipxe/ipxe.lkrn custom=
IPAPPEND 1

any ideas how to get a custom string variable passed to ipxe script?
kind regards
stefan