To work with DMI v2.1 or higher

• You will need Daylite 3.6 
• You must be running Apple Mail on Mac OS X 10.4.9 or higher including 10.5.1
  

If you are on Mac OS X 10.3.9, you can use DMI 2.0.3 which you can download here.

To work with DMI v1.5

• You will need Daylite 1.7.4 up to versions 1.9 only
  
• You must be running Apple Mail on Mac OS X 10.3.5 through 10.4.x

The current release of DMI will not run on Mac OS X 10.2.x (Jaguar).
There will be no Jaguar version.

Please note to run DMI v1.5 on Intel based Apple Mac computers, you must run Mail in Rosetta mode:

• Quit Mail
• From the Finder, open the Applications folder and locate the Mail application, select it, then choose the menu File -> Get Info
• Under the General section, check the option 'Open using Rosetta'
• Launch Mail

This will run Mail in emulation mode, which may be a little slower, but allows DMI 1.5 to integrate with it.