This is an old revision of the document!
http://www.msexchange.org/articles-tutorials/exchange-server-2010/management-administration/resource-mailboxes-exchange-2010-part1.html
http://technet.microsoft.com/en-us/library/bb124952%28v=exchg.141%29.aspx
http://technet.microsoft.com/en-us/library/bb124374%28v=exchg.141%29.aspx
Examine the mailbox:
Get-Mailbox -Identity copier@domain.tld | fl *resource*, *recipienttypedetail*
Set the mailbox as a resource account:
Set-Mailbox -Identity copier@domain.tld -Type Equipment