problem with kgdb and modules

so We upgraded our development machines from 8 stable to 9 stable. and 
now kgdb can't debug inside modules.

instead of getting anything useful, we just get:

(kgdb) bt
#0  0xffffffff81814600 in ?? () from /boot/kernel/netgraph.ko
#1  0xffffffff81812d80 in ?? () from /boot/kernel/ng_socket.ko
#2  0x0000000000000037 in ?? ()
#3  0x0000000000000002 in ?? ()
#4  0xfffffe0007176aa0 in ?? ()
#5  0xfffffe0007176aa0 in ?? ()
#6  0xffffffff818134a0 in ?? () from /boot/kernel/ng_socket.ko
#7  0xffffffff81813960 in ?? () from /boot/kernel/ng_socket.ko
#8  0xffffff860fa3cad0 in ?? ()
#9  0xffffffff808cc76e in socreate (dom=Variable "dom" is not available.
) at ../../../kern/uipc_socket.c:411



but stopping in the kernel itself, we DO see stuff..

(kgdb) break socreate
Breakpoint 1 at 0xffffffff808cc628: file ../../../kern/uipc_socket.c, 
line 372.
(kgdb) c
Continuing.



[New Thread 100198]
[Switching to Thread 100198]

Breakpoint 1, socreate (dom=32, aso=0xffffff860fa3caf0, type=2, 
proto=1, cred=0xfffffe000c63f600, td=0xfffffe011501a000) at 
../../../kern/uipc_socket.c:372
372             if (proto)
(kgdb) bt
#0  socreate (dom=32, aso=0xffffff860fa3caf0, type=2, proto=1, 
cred=0xfffffe000c63f600, td=0xfffffe011501a000) at 
../../../kern/uipc_socket.c:372
#1  0xffffffff808cf710 in sys_socket (td=0xfffffe011501a000, 
uap=0xffffff860fa3cbc0) at ../../../kern/uipc_syscalls.c:199
#2  0xffffffff80b5599a in amd64_syscall (td=0xfffffe011501a000, 
traced=0) at subr_syscall.c:131
#3  0xffffffff80b40b57 in Xfast_syscall () at 
../../../amd64/amd64/exception.S:387
#4  0x00000008011c82ac in ?? ()



etc.

it looks as if modules no longer have stack frames compiled in.
does anyone know the culprit?