[Mimedefang] Mimedfang memory problems since upgrade to 2.45

[Mason Rob (NHS Information Authority)]

Hi,

I'm running Sendmail, SA-3, MD-2.45 on FreeBSD 5.3 RC1.  
Since upgrading to this config I get the following errors 
(about 1 in 5 emails):

Nov  3 06:06:04 huygens mimedefang-multiplexor[18496]: Slave 
0 stderr: Out of memory during request for
Nov  3 06:06:04 huygens mimedefang-multiplexor[18496]: Slave 
0 stderr: 20592 bytes, total sbrk() is 27375616 bytes!
Nov  3 06:06:07 huygens mimedefang-multiplexor[18496]: Slave 
0 died prematurely -- check your filter rules
Nov  3 06:06:07 huygens mimedefang-multiplexor[18496]: Reap: 
Idle slave 0 (pid 22437) exited normally with status 1 (SLAVE 
DIED UNEXPECTEDLY)
Nov  3 06:06:07 huygens mimedefang-multiplexor[18496]: Slave 
0 resource usage: req=4, scans=4, user=20.896, sys=1.940, 
nswap=0, majflt=2183, minflt=20032, maxrss=23784, bi=448, 
bo=16
Nov  3 06:06:07 huygens mimedefang[18508]: Error from 
multiplexor: ERR No response from slave
Nov  3 06:06:07 huygens sm-mta[25322]: iA36616S025322: 
Milter: data, reject=451 4.3.2 Please try again later
Nov  3 06:06:07 huygens sm-mta[25322]: iA36616S025322: 
to=<masonr at localhost>, delay=00:00:06, pri=50363, stat=Please 
try again later
Nov  3 06:06:10 huygens mimedefang-multiplexor[18496]: 
Starting slave 0 (pid 25324) (2 running): Bringing slaves up 
to minSlaves (2)

I've trawled through the archives but can't find anything 
directly relevent.  My mimedefang-filter is standard (as 
distributed aside from email addresses).

Any pointers apprciated,

Rob

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