Another one, confirming existence in 2.6.32-45. System has recently been upgraded from oldstable. No actual problems detected, just the messages.

dorfl:~# cat /proc/version
Linux version 2.6.32-5-686-bigmem (Debian 2.6.32-45) (dannf@debian.org) (gcc version 4.3.5 (Debian 4.3.5-4) ) #1 SMP Sun May 6 04:39:05 UTC 2012


dorfl:~# grep md /var/log/dmesg
[*** 4.376264] md: raid0 personality registered for level 0
[*** 4.378696] md: raid1 personality registered for level 1
[*** 4.395482] mdadm: sending ioctl 1261 to a partition!
[*** 4.395484] mdadm: sending ioctl 1261 to a partition!
[*** 4.395632] mdadm: sending ioctl 1261 to a partition!
[*** 4.395636] mdadm: sending ioctl 1261 to a partition!
[*** 4.413568] mdadm: sending ioctl 1261 to a partition!
[*** 4.413570] mdadm: sending ioctl 1261 to a partition!
[*** 4.413674] mdadm: sending ioctl 1261 to a partition!
[*** 4.413676] mdadm: sending ioctl 1261 to a partition!
[*** 4.413788] mdadm: sending ioctl 800c0910 to a partition!
[*** 4.413791] mdadm: sending ioctl 800c0910 to a partition!
[*** 4.417101] md: md0 stopped.
[*** 4.417847] md: bind<sdb1>
[*** 4.417967] md: bind<sda1>
[*** 4.418703] raid1: raid set md0 active with 2 out of 2 mirrors
[*** 4.418717] md0: detected capacity change from 0 to 4301717504
[*** 4.419235]* md0:
[*** 4.421492] md: md1 stopped.
[*** 4.422680] md: bind<sdb2>
[*** 4.422803] md: bind<sda2>
[*** 4.423530] raid1: raid set md1 active with 2 out of 2 mirrors
[*** 4.423544] md1: detected capacity change from 0 to 2154954752
[*** 4.424045]* md1: unknown partition table
[*** 4.432681] md: md2 stopped.
[*** 4.433223] md: bind<sdb3>
[*** 4.433337] md: bind<sda3>
[*** 4.434080] raid1: raid set md2 active with 2 out of 2 mirrors
[*** 4.434094] md2: detected capacity change from 0 to 743696826368
[*** 4.434621]* md2:
[*** 8.113984] Adding 4200888k swap on /dev/md0.* Priority:-1 extents:1 across:4200888k
[*** 9.392446] EXT3 FS on md1, internal journal


dorfl:~# grep md /var/log/syslog
Jun 19 08:38:50 dorfl kernel: [1806233.314730] mdadm: sending ioctl 1261 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.314734] mdadm: sending ioctl 1261 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.365106] mdadm: sending ioctl 1261 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.365110] mdadm: sending ioctl 1261 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.395145] mdadm: sending ioctl 1261 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.395150] mdadm: sending ioctl 1261 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.419005] mdadm: sending ioctl 1261 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.419010] mdadm: sending ioctl 1261 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.451229] mdadm: sending ioctl 800c0910 to a partition!
Jun 19 08:38:50 dorfl kernel: [1806233.451233] mdadm: sending ioctl 800c0910 to a partition!


--
Bier met grenadyn
Is als mosterd by den wyn
Sy die't drinkt, is eene kwezel
Hy die't drinkt, is ras een ezel