procmail kill problems in dmesg?

[Matt Juszczak]

Getting flooded with:

pid 65128 (procmail), uid 3005: exited on signal 11
pid 65138 (procmail), uid 806: exited on signal 11
pid 65142 (procmail), uid 24112: exited on signal 11
pid 65143 (procmail), uid 11977: exited on signal 11
pid 65146 (procmail), uid 29601: exited on signal 11
pid 65149 (procmail), uid 18864: exited on signal 11
pid 65239 (procmail), uid 19458: exited on signal 11
pid 65240 (procmail), uid 22242: exited on signal 11
pid 65242 (procmail), uid 2005: exited on signal 11
pid 65244 (procmail), uid 14209: exited on signal 11
pid 65243 (procmail), uid 22118: exited on signal 11
pid 65246 (procmail), uid 17854: exited on signal 11
pid 65247 (procmail), uid 18156: exited on signal 11
pid 65248 (procmail), uid 16655: exited on signal 11
pid 65249 (procmail), uid 18389: exited on signal 11
pid 65250 (procmail), uid 11977: exited on signal 11
pid 65251 (procmail), uid 11110: exited on signal 11
pid 65267 (procmail), uid 1762: exited on signal 11
pid 65349 (procmail), uid 11977: exited on signal 11
pid 65350 (procmail), uid 1982: exited on signal 11
pid 65351 (procmail), uid 15324: exited on signal 11
pid 65433 (procmail), uid 3183: exited on signal 11
pid 65435 (procmail), uid 12280: exited on signal 11
pid 65436 (procmail), uid 11977: exited on signal 11
pid 65534 (procmail), uid 2005: exited on signal 11
pid 65535 (procmail), uid 22662: exited on signal 11
pid 65537 (procmail), uid 24477: exited on signal 11
pid 65538 (procmail), uid 1397: exited on signal 11
pid 65540 (procmail), uid 11645: exited on signal 11
pid 65612 (procmail), uid 21744: exited on signal 11
pid 65621 (procmail), uid 24147: exited on signal 11
pid 65724 (procmail), uid 2005: exited on signal 11
pid 65725 (procmail), uid 580: exited on signal 11
pid 65726 (procmail), uid 11977: exited on signal 11

This is a high traffic mail server .... is this normal?  Why does procmail 
sometimes exit on signal 11 like this?

Thanks!

-Matt