Postfix: fatal: getrlimit: Operation not permitted

[colona <colona0@gmail.com>]

Hi,

I use wheezy armel (2.6.36.2) on a sheevaplug and since I updated my
system yesterday I can't send or receive emails anymore with postfix.

This is what I get when I try to send an email :
> postdrop: fatal: getrlimit: Operation not permitted
> sendmail: warning: command "/usr/sbin/postdrop -r" exited with status 1
> sendmail: fatal: colona(1001): unable to execute /usr/sbin/postdrop -r: Success

And these three error messages are added every minute to my syslog and
mail.err/.warn :
> postfix/local[24723]: fatal: unable to determine open file limit
> postfix/master[24536]: warning: process /usr/lib/postfix/local pid 24723 exit status 1
> postfix/master[24536]: warning: /usr/lib/postfix/local: bad command startup -- throttling

What might be relevant in the apt history (I can provide the full log) :
> Upgrade: libc-bin:armel (2.11.2-11, 2.13-4),
> libc6-dev:armel (2.11.2-11, 2.13-4), libc6:armel (2.11.2-11, 2.13-4)

ulimit -a does work and give "normal" values. Everything else is working
fine, the stuff I use daily at least.
I asked on #debian@freenode and #debian-arm@oftc but we couldn’t find
any solution and I don’t know what to do now.

Thank you.
-- 
Ivan "Colona" Delalande