Problem compiling custom kernel with default values

Hello list members,

I have the following problem in compiling a custom kernel:

* plain Vanilla kernel 2.4.20 patched with squashdfs and supermount 
* .config from the original PXES 0.9

Problem: It is not possible to compile support for USB-Storage devices.

When compiling with that config I encounter the following error
(anything related to SCSI included):

gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsicam  -c -o scsicam.o
scsicam.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_proc  -c -o scsi_proc.o
scsi_proc.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_error  -c -o scsi_error.o
scsi_error.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_obsolete  -c -o
scsi_obsolete.o scsi_obsolete.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_queue  -c -o scsi_queue.o
scsi_queue.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_lib  -c -o scsi_lib.o
scsi_lib.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_merge  -c -o scsi_merge.o
scsi_merge.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_dma  -c -o scsi_dma.o
scsi_dma.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_scan  -c -o scsi_scan.o
scsi_scan.c
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=scsi_syms  -DEXPORT_SYMTAB -c
scsi_syms.c
ld -m elf_i386 -r -o scsi_mod.o scsi.o hosts.o scsi_ioctl.o constants.o
scsicam.o scsi_proc.o scsi_error.o scsi_obsolete.o scsi_queue.o
scsi_lib.o scsi_merge.o
scsi_dma.o scsi_scan.o scsi_syms.o
gcc -D__KERNEL__ -I/usr/src/linux-2.4.20-6pxes/include -Wall
-Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common
-fomit-frame-pointer -pipe
-mpreferred-stack-boundary=2 -march=i586 -DMODULE -DMODVERSIONS -include
/usr/src/linux-2.4.20-6pxes/include/linux/modversions.h  -nostdinc
-iwithprefix include -DKBUILD_BASENAME=sd  -c -o sd.o sd.c
sd.c: In function `sd_init_onedisk':
sd.c:823: `SDev' undeclared (first use in this function)
sd.c:823: (Each undeclared identifier is reported only once
sd.c:823: for each function it appears in.)
make[2]: *** [sd.o] Fehler 1
make[2]: Verlassen des Verzeichnisses Verzeichnis
>/usr/src/linux-2.4.20-6pxes/drivers/scsi<
make[1]: *** [_modsubdir_scsi] Fehler 2
make[1]: Verlassen des Verzeichnisses Verzeichnis
>/usr/src/linux-2.4.20-6pxes/drivers<
make: *** [_mod_drivers] Fehler 2
[root@devtux linux]#

(translation for the non-germans :)):
"Fehler" = "Error"
"Verlassen des Verzeichnisses" = "Leaving directory"

I did anything else correct. As soon as I disable anything under SCSI
except the general "SCSI support" the kernel compiles and runs fine with
PXES.
Problem then is, that I cannot use USB-Storage devices.
From the modules under ...2.4.20-12pxes/kernel/drivers/scsi in PXES 0.9
I see there are:
ide-scsi.o
scsi_mod.o
sd_mod.o

scsi_mod.o is the general SCSI support. sd_mod.o however is the "SCSI
disk support" which doesn't want to compile. (I didn't find out so far
how ide-scsi.o is be compiled)

Can anyone give me a hint - or can you have a look at your current
config Diego if the one provided with PXES 0.9 is the wrong one?

Thanks a lot in advance,
Sascha