plague of computation errors (signal 4)

I have had an alarming number of seti@home work units terminate with computation errors over the last week or so. All seem to be reporting that "process got signal 4". This is happening on one (and only one) computer - see below.

I have reinstalled the latest BOINC manager, to no avail.

Any suggestions as to why this is happening and what might be done to stop it happening?

Typical error:

Stderr output

<core_client_version>6.10.58</core_client_version>
<![CDATA[
<message>
process got signal 4
</message>
<stderr_txt>
Unrecognized XML in parse_init_data_file: hostid
Skipping: 4986537
Skipping: /hostid
Unrecognized XML in parse_init_data_file: starting_elapsed_time
Skipping: 0.000000
Skipping: /starting_elapsed_time
Unrecognized XML in parse_init_data_file: hostid
Skipping: 4986537
Skipping: /hostid
Unrecognized XML in parse_init_data_file: starting_elapsed_time
Skipping: 0.000000
Skipping: /starting_elapsed_time
setiathome_enhanced 6.00 XCode GCC 4.0.1 (Apple Inc. build 5465) i386

libboinc: 6.2.18
libboinc: 6.2.18

Computer details: (mid 2009 macbook pro 17")

Created 12 Jun 2009 13:27:16 UTC
Total credit 474,573
Average credit 745.39
Cross project credit
CPU type GenuineIntel
Intel(R) Core(TM)2 Duo CPU T9600 @ 2.80GHz [x86 Family 6 Model 23 Stepping 10]
Number of processors 2
Coprocessors ---
Operating System Darwin
10.5.0
BOINC version 6.10.58
Memory 4096 MB
Cache 976.56 KB
Swap space 210982.95 MB
Total disk space 465.44 GB
Free Disk Space 205.79 GB
Measured floating point speed 3210.67 million ops/sec
Measured integer speed 7210.05 million ops/sec
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not sure what it all means but its not good for sure
____________
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