libavcodec52 0.7.1 broke libasound_module_pcm_a52.so (from …

It appears that the libavcodec52 0.7.1 broke alsa AC-3 encoding. After
the upgrade a setup that was working just fine before became silent.
Debugging it I ran into this:

$ aplay /home/user/music/5_DRAX_-_Resolution_R3\&R4AR.wav
Playing WAVE '/home/user/music/5_DRAX_-_Resolution_R3&R4AR.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo
[ac3 @ 0x1a72360] Specified sample_fmt is not supported.
aplay: set_params:1116: Unable to install hw params:
ACCESS: RW_INTERLEAVED
FORMAT: S16_LE
SUBFORMAT: STD
SAMPLE_BITS: 16
FRAME_BITS: 32
CHANNELS: 2
RATE: 48000
PERIOD_TIME: 32000
PERIOD_SIZE: 1536
PERIOD_BYTES: 6144
PERIODS: 10
BUFFER_TIME: 320000
BUFFER_SIZE: 15360
BUFFER_BYTES: 61440
TICK_TIME: 0

$ sudo dpkg -i libavcodec52_0.6.3-0.0_amd64.deb
dpkg: warning: downgrading libavcodec52 from 5:0.7.1-0.0 to 5:0.6.3-0.0.
(Reading database ... 218630 files and directories currently installed.)
Preparing to replace libavcodec52 5:0.7.1-0.0 (using
libavcodec52_0.6.3-0.0_amd64.deb) ...
Unpacking replacement libavcodec52 ...
Setting up libavcodec52 (5:0.6.3-0.0) ...

$ aplay /home/user/music/5_DRAX_-_Resolution_R3\&R4AR.wav
Playing WAVE '/home/user/music/5_DRAX_-_Resolution_R3&R4AR.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo

...and the audio plays ok now.

I'm using debian unstable and kernel 2.6.39.3. I have audio routed via
HDMI, and thus I've set up alsa so that all non-AC-3 audio goes thru the
a52 encoding:

pcm.Filter_A52Encode {
     type a52
     bitrate 448
     card 0
}
...etc...

I presume something is wrong with libavcodec52 0.7.1 AC-3 encoding since
it fails with "[ac3 @ 0x1a72360] Specified sample_fmt is not supported."

Some related package versions:
alsa-utils                        1.0.23-5+b1
libasound2                        1.0.24.1-2
libasound2-plugins                1.0.24-2

Regards,
--
l=2001;main(i){float o,O,_,I,D;for(;O=I=l/571.-1.75,l;)for(putchar(--l%80?
i:10),o=D=l%80*.05-2,i=31;_=O*O,O=2*o*O+I,o=o*o-_+D,o+_+_<4+D&i++<87;);puts
(" Harry 'Piru' Sintonen <sintonen@???> http://www.iki.fi/sintonen");}