[Dovecot] Dovecot + Sendmail + virtusertable

Hello,

I was wondering if there was a way to have dovecot authenticate using sendmail's virtusertable to map virtual users to system users. My goal is to allow virtual users (bob@domain.com) to authenticate via pop or imap using the full user@domain scheme. I tried enabling 'vpopmail' as passdb and userdb in the default namespace but I get this error:

dovecot: May 15 23:05:21 Error: auth(default): Unknown passdb type 'vpopmail'

Please advise.

Thanks, Chris