From: "MauMau" <maumau307(at)gmail(dot)com>
> OK, I'll take this approach.  That is:
I did as Tom san suggested.  Please review the attached patch.  I chose as 
common errnos by selecting those which are used in PosttgreSQL source code 
out of the error numbers defined in POSIX 2013.
As I said, lack of %m string has been making troubleshooting difficult, so I 
wish this to be backported at least 9.2.
Regards
MauMau