Replicate mailboxes between exchange 2003 and 2007?

we can switch to the 2007 virtual server for a day or two until the 'main' server gets back online

ITs not clear what you intend to do.by "main" server do u mean "the server recicing or sending emails" or the server "having mailboxes"
let me know

'main' server is defined as both since it is our one and only exchange server, hence the need for this virtual server. I would like the virtual server to run exchange 2007 and i would like to use this virtual server if it will take more than a few hours to bring the 'main' server back online.

bottom line, we only have licensing for 1 copy of exchange 2003 and 1 copy of exchange 2007. i'm trying to figure out how we can use it to our best advantage and provide some sort of backup if one server goes down for an extended period of time.

bottom line, we only have licensing for 1 copy of exchange 2003 and 1 copy of exchange 2007. i'm trying to figure out how we can use it to our best advantage and provide some sort of backup if one server goes down for an extended period of time.
answer:-
CO-EXISTANCE of exchagne 2003 and exchagne 2007 is fully supported so you dont really need to bring one ONLINE and the other OFFLINE.
ONE license is sufficient for all the roles you need.MAILBOX,CAS,HUB.and move mailboxes from exchagne 2003 to 2007.
thanks.

i though it wasnt possible to host the same mailboxes on both 2007 and 2003 at the same time.

From what i understand it looks like you're saying to move the mailboxes to the 2007 box, but how does that let me switch over to another server if that server goes down for an extended period of time?

From what i understand it looks like you're saying to move the mailboxes to the 2007 box, but how does that let me switch over to another server if that server goes down for an extended period of time?

YOU CAN USE THE additional hardware for disaster recovery purposes[provided ur hardware supports 64 bit OS]
see this link
http://technet.microsoft.com/en-us/library/bb123496(EXCHG.80).aspx
thanks.

Maybe im not explaining this correctly.

I have one physical machine running exchange 2003 on a 32bit system(which i am calling the 'main' server). I can create a virtual machine with a 64-bit OS for exchange 2007.

If the 'main' server goes offline for hardware failure or database corruption, it will take about 2 days to get it back online becuase i dont have an onsite copy of the exchange database. My goal is to somehow have an onsite copy of the exchang database.

I was thinking if i install exchange 2007 on the 64bit virtual machine maybe i can replicate mailbox/exchange database information between the 2003 physical machine and 2007 virtual machine so when the 2003 machine goes down becuase of failure i can activate the virtual machine until i can recover from the initial failure so staff can still have access to their mailbox and send/receive email.

Then what if i have a great server then the motherboard dies for some reason? I cant just say ok mail wont work for the rest of the day. There is no kind of replication of any kind that can be setup between the two servers?

Motherboard failure is unusual, once you are past the initial time. If the server is that critical then you put the server on a four hour response time. If that is still too long then buy a second chassis for standby.

The longer you can be without email, the cheaper it is.

There is no replication capability built in to Exchange without using clustering technologies.

Simon.