ipop3 mail error

I got an error when i try to sent a e-mail using sendmail.

Jul 22 00:36:04 mail ipop3d[846]: [ID 368680 mail.info] Error opening or locking
INBOX user=mie host=[xxx.xxx.xxx.xxx]

INBOX user=mdfaizal host=[xxx.xxx.xxx.xxx]
ul 22 00:36:31 mail ipop3d[856]: [ID 621598 mail.info] Mailbox lock file /tmp/.
20000e.f open failure: Permission denied


Jul 22 00:36:12 mail ipop3d[849]: [ID 702911 mail.debug] Mailbox is open by anot
her process, access is readonly
Jul 22 00:36:12 mail ipop3d[849]: [ID 702911 mail.debug] Expunge ignored on read
only mailbox


any body.. help me...

some other process/user is alreadfy connected to the server for the mailbox you're trying to access