I'm seeing this:

 /etc/cron.daily/sa-update:
ERROR: spamd did not start...
run-parts: /etc/cron.daily/sa-update exited with return code 1

This seems to come from this part of the script:
84         # verify it's running
85         SA_PID=`pidof spamd`
86         if [ -z "$SA_PID" ]; then
87             echo "ERROR: spamd did not start..."

And indeed pidof does not return the correct pid even though spamd is running:
$ ps axf | grep spamd
27042 pts/0    S+     0:00              \_ grep --color spamd
26227 ?        Ss     0:10 /usr/bin/spamd --pidfile /var/run/spamd.pid -d -c -m5 -H --syslog=/var/log/spamassassin/spamd.log --socketpath=/var/run/spamd/spamd.socket
26234 ?        S      0:00  \_ spamd child
26235 ?        S      0:00  \_ spamd child
$ pidof spamd
$ echo $?
1

strace shows:
...
open("26227/stat", O_RDONLY)            = 4
fstat64(4, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7776000
read(4, "26227 (/usr/bin/spamd ) S 1 2622"..., 1024) = 248
close(4)                                = 0
munmap(0xb7776000, 4096)                = 0
open("26227/cmdline", O_RDONLY)         = 4
fstat64(4, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7776000
read(4, "/usr/bin/spamd --pidfile /var/ru"..., 1024) = 138
read(4, "", 1024)                       = 0
read(4, "", 1024)                       = 0
close(4)                                = 0
munmap(0xb7776000, 4096)                = 0
readlink("/proc/26227/exe", "/usr/bin/perl5.14.2", 4096) = 19
open("26234/stat", O_RDONLY)            = 4
fstat64(4, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7776000
read(4, "26234 (spamd child) S 26227 2622"..., 1024) = 242
close(4)                                = 0
munmap(0xb7776000, 4096)                = 0
open("26234/cmdline", O_RDONLY)         = 4
fstat64(4, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7776000
read(4, "spamd child", 1024)            = 11
read(4, "", 1024)                       = 0
read(4, "", 1024)                       = 0
close(4)                                = 0
munmap(0xb7776000, 4096)                = 0  
readlink("/proc/26234/exe", "/usr/bin/perl5.14.2", 4096) = 19
open("26235/stat", O_RDONLY)            = 4
fstat64(4, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7776000
read(4, "26235 (spamd child) S 26227 2622"..., 1024) = 242
close(4)                                = 0  
munmap(0xb7776000, 4096)                = 0
open("26235/cmdline", O_RDONLY)         = 4
fstat64(4, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7776000
read(4, "spamd child", 1024)            = 11
read(4, "", 1024)                       = 0
read(4, "", 1024)                       = 0
close(4)                                = 0
munmap(0xb7776000, 4096)                = 0
readlink("/proc/26235/exe", "/usr/bin/perl5.14.2", 4096) = 19
...