We have a user with mailbox@domain.tld who would like to have the Out of Office auto notification use alias@domain.tld for both the From: and Reply To: fields. I have done the following...
[zimbra@host ~]$ zmprov ga mailbox@domain.tld | egrep '^zimbraPref.+Address'
zimbraPrefAutoAddAddressEnabled: TRUE
zimbraPrefFromAddress: alias@domain.tld
zimbraPrefOutOfOfficeDirectAddress: alias@domain.tld
zimbraPrefReplyToAddress: alias@domain.tld
[zimbra@host ~]$
When it sends an OoO message, the Reply To: field is correct, but the From: field still references mailbox@domain.tld

I know that one way to make it work is to switch the mailbox and alias names, but we prefer not doing that to maintain a naming consistency.

Any thoughts or suggestions would be greatly appreciated.

My environment
[zimbra@host ~]$ zmcontrol -v ; uname -a ; cat /etc/redhat-release
Release 5.0.22_GA_3210.RHEL5_64_20100125181151 CentOS5_64 NETWORK edition
Linux host.domain.tld 2.6.18-128.1.16.el5 #1 SMP Tue Jun 30 06:07:26 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux
CentOS release 5.3 (Final)
[zimbra@host ~]$