Stability issues / UFS based panic on recent CURRENT (03/22)

Hi guys,
	I'm noticing some stability issues in recent days with two cases:
	1. I typically use vuze / xchat2, and when I bring the network  
interfaces down once, and poll a few times (ifconfig msk0) my system  
freezes, which forces me to reboot. Don't have any hard data right  
now, but I hit this ~10% of the time.
	2. It takes about 15 minutes to fsck my entire system and sometimes I  
get impatient and startup x11 right away. Unfortunately when I was  
opening up my browser, my system froze again and subsequently panicked  
with UFS related tracebacks. Here's the output:

[root_at_orangebox /scratch/crash]# kgdb /boot/kernel/kernel vmcore.3
GNU gdb 6.1.1 [FreeBSD]
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and  
you are
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This GDB was configured as "i386-marcel-freebsd"...

Unread portion of the kernel message buffer:
dev = ad6s1g, block = 1446736, fs = /usr/home
panic: ffs_blkfree: freeing free block
cpuid = 1
Uptime: 32m29s
Physical memory: 3318 MB
Dumping 140 MB: 125 109 93 77 61 45 29 13

Reading symbols from /boot/kernel/vesa.ko...Reading symbols from /boot/ 
kernel/vesa.ko.symbols...done.
done.
Loaded symbols for /boot/kernel/vesa.ko
#0  doadump () at pcpu.h:246
246	pcpu.h: No such file or directory.
	in pcpu.h
(kgdb) bt
#0  doadump () at pcpu.h:246
#1  0xc0620508 in boot (howto=260) at /usr/src/sys/kern/ 
kern_shutdown.c:420
#2  0xc06207ee in panic (fmt=Variable "fmt" is not available.
) at /usr/src/sys/kern/kern_shutdown.c:576
#3  0xc079e62a in ffs_blkfree (ump=0xc6c0bc00, fs=0xc6acc800,  
devvp=0xc6c50c90, bno=1446736, size=16384, inum=354012) at /usr/src/ 
sys/ufs/ffs/ffs_alloc.c:1914
#4  0xc07b1df2 in indir_trunc (freeblks=0xc7127b00, dbn=5737856,  
level=0, lbn=12, countp=0xe6c83c54) at /usr/src/sys/ufs/ffs/ 
ffs_softdep.c:2919
#5  0xc07b2057 in handle_workitem_freeblocks (freeblks=0xc7127b00,  
flags=0) at /usr/src/sys/ufs/ffs/ffs_softdep.c:2768
#6  0xc07b3618 in process_worklist_item (mp=0xc6bfda00, flags=Variable  
"flags" is not available.
) at /usr/src/sys/ufs/ffs/ffs_softdep.c:957
#7  0xc07b8662 in softdep_process_worklist (mp=0xc6bfda00, full=0) at / 
usr/src/sys/ufs/ffs/ffs_softdep.c:840
#8  0xc07b8c55 in softdep_flush () at /usr/src/sys/ufs/ffs/ 
ffs_softdep.c:751
#9  0xc05ff1f1 in fork_exit (callout=0xc07b8967 <softdep_flush>,  
arg=0x0, frame=0xe6c83d38) at /usr/src/sys/kern/kern_fork.c:821
#10 0xc082c350 in fork_trampoline () at /usr/src/sys/i386/i386/ 
exception.s:270

I'll be glad to provide additional data -- please CC my FreeBSD alias  
so I can keep track of when folks email me as this mailing address  
gets a fair amount of traffic.

Thanks!
-Garrett