"Out of memory" in procmail log file

Hello all,
I use procmail v3.11pre7.
There is message in procmail log file.

procmail: Out of memory
buffer 0: "hcode -dk -m | formail -A \
              "X-Automatic-Korean-Mail-Conversion: iso-2022-kr to
euc-kr" "
buffer 1: "hcode -dk -m | formail -A \
              "X-Automatic-Korean-Mail-Conversion: iso-2022-kr to
euc-kr" "
  Folder: **Bounced**



What makes this messges appear?
If there is any one who know the reason, Please send the mail to
dejavu(_at_)bora(_dot_)dacom(_dot_)co(_dot_)kr(_dot_)

Any suggestions would be appreciated.
I wait for your reply.