Lock file problems

Can someone help me? I'm getting these in my logfile and I don't
understand why (perhaps the permissions are not set correctly?):

procmail: Assigning "LOCKFILE=/tmp/micah.lockfile"
procmail: Locking "/tmp/mgmead.lockfile"
procmail: Locking "/var/mail/micah.lock"
procmail: Error while writing to "/var/mail/_FU0Gsmmedia.c"
procmail: [1936] Thu Aug 22 21:32:06 1996
etc
etc
etc

for a while then it gives me:
procmail: Lock failure on "/var/mail/micah.lock"
procmail: Assigning "LASTFOLDER=/var/mail/micah"
procmail: Opening "/var/mail/micah"
procmail: Acquiring kernel-lock
> From micah(_at_)smmedia(_dot_)com  
 Subject: test
  Folder: /var/mail/micah
etc...


??

Thanks,
Micah

_______________________________________________________________________________
Micah Johan Eckman Anderson                             
micah(_at_)smmedia(_dot_)com
Sr. Systems Administrator                               1-888-614-3709
Schmidt Mead Media, Inc.                                
pagemicah(_at_)smmedia(_dot_)com        
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