lockmgr: thread 0xc06f50e0 unlocking unheld lock

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	The Regents of the University of California. All rights reserved.
FreeBSD 7.0-CURRENT #1: Mon Jan  2 09:51:43 CST 2006
     davidxu_at_apple.my.domain:/usr/src/sys/i386/compile/gennw
ACPI APIC Table: <DELL   9100   >
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Pentium(R) D CPU 2.80GHz (2793.01-MHz 686-class CPU)
   Origin = "GenuineIntel"  Id = 0xf44  Stepping = 4
 
Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
   Features2=0x641d<SSE3,RSVD2,MON,DS_CPL,CNTX-ID,CX16,<b14>>
   AMD Features=0x20100000<NX,LM>
   Logical CPUs per core: 2
real memory  = 1072218112 (1022 MB)
avail memory = 1040052224 (991 MB)
FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
  cpu0 (BSP): APIC ID:  0
  cpu1 (AP): APIC ID:  1
ioapic0: Changing APIC ID to 8
ioapic0 <Version 2.0> irqs 0-23 on motherboard
lapic0: Forcing LINT1 to edge trigger
lockmgr: thread 0xc06f50e0 unlocking unheld lock
KDB: stack backtrace:
kdb_backtrace(c069e6f9,c06f50e0) at kdb_backtrace+0x29
lockmgr(c06ff8e8,6,c06ff90c,c06f50e0,c0c20d3c) at lockmgr+0x589
smb_co_unlock(c06ff8e0,0,c06f50e0,c0c20d48,c05ac441) at smb_co_unlock+0x1d
smb_sm_init(c4acf880,c0c20d74,c0507c4b,c4acf880,0) at smb_sm_init+0x31
nsmb_dev_load(c4acf880,0,0,c06f5c20,0) at nsmb_dev_load+0x1d
module_register_init(c06dd404,c1ec00,c1e000,0,c0433455) at 
module_register_init+0x4b
mi_startup() at mi_startup+0x96
begin() at begin+0x2c
netsmb_dev: loaded

I have following options in kernel config file:
options         NETSMB
options         NETSMBCRYPTO
options         LIBMCHAIN
options         LIBICONV
options         SMBFS