x86 Windows Vista RTM/SP1/SP2
x64 Windows Vista RTM/SP1/SP2
x86 Windows Server 2008 SP1/SP2
x64 Windows Server 2008 SP1/SP2
x86 Windows 7
x64 Windows 7
x64 Windows Server 2008 R2

How to add x64 (64 bit) drivers on a x86 (32 bit) Windows Server 2003 or Windows Server 2008
Note: Also works for x86 Windows XP or Vista print "server".

Step 1. Share a x86 print queue out
On a x86 Windows XP/Vista/Windows7 or a x86 Windows Server 2003/Server 2008
Login with the Domain Administrator account or Local Admin account
Click on Start, Control Panel, Printers,
Press the ALT button or Click on Organize, Layout, Menu Bar
Click on File
Click on Run as administrator
Click on Add Printer...
Choose "Add a local printer" or "Add a network, wireless or Bluetooth printer"
And go thru the rest of the steps to install a printer and make sure that you share
it for example PrintShare1.

Step 2. Add the x86 print driver
On the x64 Windows Server 2008 SP1/SP2/R2
Login with the Domain Administrator account
Click on Start, \\x86W2K8 PrintServer (or a x86 W2K3)
Double click on "Printers"
Right click on the PrintShare1
Click on the "Sharing" tab
Click on the "Additional Drivers..."
Check the box for 'x64 Type 3 - User Mode'
Click on Ok
Click on Close