Why am I getting this error?

Hello 

I use procmail to sort all of my incoming email and it usually works really
well but sometime I get some errors and I was wandering why  I have  pasted
the error bellow. 

Thanks for your help



procmail: Error while writing to "Mailing_List/Computer/squirrelmail"
procmail: Truncated file to former size
procmail: Error while writing to "Mailing_List/Computer/squirrelmail"
procmail: Truncated file to former size
procmail: Error while writing to "Mailing_List/Computer/squirrelmail"
procmail: Truncated file to former size
> From squirrelmail-devel-admin(_at_)lists(_dot_)sourceforge(_dot_)net  Sat Apr  
> 9 11:06:12
2005
 Subject: [SM-DEVEL] It may be time to ditch GPL
  Folder: /var/mail/edward                           5560



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