dump hangs on 7.1

[Len Conrad]

FreeBSD 7.1-RELEASE #0: Thu Jan  1 14:37:25 UTC 2009     root at logan.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

CPU: Intel(R) Xeon(R) CPU           E5420  @ 2.50GHz (2496.26-MHz 686-class CPU) 
  Origin = "GenuineIntel"  Id = 0x1067a  Stepping = 10
  AMD Features=0x20100000<NX,LM>
  AMD Features2=0x1<LAHF>
  Cores per package: 4
real memory  = 3484745728 (3323 MB)
avail memory = 3405537280 (3247 MB)
ACPI APIC Table: <DELL   PE_SC3  >
FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
 cpu0 (BSP): APIC ID:  0
 cpu1 (AP): APIC ID:  1
 cpu2 (AP): APIC ID:  2
 cpu3 (AP): APIC ID:  3


/sbin/dump -0uanL -f - / | ssh dump_images at xxx.net dd of=/var/ftp/dump_images/mx1-root-test

dump has completed only once. Several other dumps have all gotten under way, target file is created and increases until the hang.  

CTRL-C gets back to shell,eg:

  DUMP: Date of this level 0 dump: Fri Jul 10 10:25:33 2009
  DUMP: Date of last level 0 dump: the epoch
  DUMP: Dumping snapshot of /dev/da0s1d (/usr) to standard output
  DUMP: mapping (Pass I) [regular files]
  DUMP: mapping (Pass II) [directories]
  DUMP: estimated 1713942 tape blocks.
  DUMP: dumping (Pass III) [directories]
  DUMP: dumping (Pass IV) [regular files]
^C  DUMP: Interrupt received.
  DUMP: Do you want to abort dump?: ("yes" or "no") Killed by signal 2.
  DUMP: Broken pipe
  DUMP: The ENTIRE dump is aborted.

Hangs always in Pass IV

Plenty of google hits for "dump hang freebsd 7.1" but I can't find one with a solution.

Len