Upgraded from v262 to the latest (v413) and got:

hijack(12): memory violation at pc=0x020045a0, lr=0x02004548 (bad address=0x464c4587, code 2)
pc : [<020045a0>] lr : [<02004548>]
sp : bffffe80 ip : bffffea0 fp : bffffe9c
r10: 020006c8 r9 : 00000000 r8 : 0202f010
r7 : 0203ff30 r6 : 464c457f r5 : 0203ff20 r4 : 00000010
r3 : 00001069 r2 : 00000010 r1 : 00001068 r0 : 464c457f
Flags: nZCv IRQs on FIQs on Mode USER_32 Segment user
Control: C0F3D17D Table: C0F3D17D DAC: 00000015
Function entered at [<02004578>] from [<02004548>]
r7 = 00000000 r6 = 020000C0 r5 = 0203FF20 r4 = 464C457F
Function entered at [<020044a0>] from [<020009c0>]
r5 = BFFFFF74 r4 = 00000001
Function entered at [<020006c8>] from [<02000b64>]
Function entered at [<02000a88>] from [<02000104>]
r10 = 00000000 r8 = 00000000 r7 = 00000000 r6 = 00000000
r5 = 00000000 r4 = 00000000

Machine runs, but network is unusable. Maybe one or two pings will get through with > 1000 ms latency, but nothing much more.

Rolled over to the v410/ext3 build, and the same thing. About to go back to v262. Anyone have any ideas?