Convert Apple PS@ plug into usb.

Although it is the same round shape as the PS2 connector, that mouse has an Apple Desktop Bus ADB connector, and uses ADB protocol. I don't think the PS2 pins are in the same locations. It will definitely never work again if you cut the end off and solder anything else on it.

If you really, really love it, there were some USB-to-ADB adapters sold, but when new they sold for about US$35, and they are no longer made. I think Keyspan was the main maker.

Griffin made the iMate, which enabled the connection of an ADB device to a USB port. Here's one listed at eBay, that is going to end soon. Apparently there are third-party drivers available that are compatible with your Intel-based 2009 iMac running OS 10.6.6, since the Griffin driver is compatible with OS 10.3.9 or earlier. For what it's worth, another eBay listing indicates that no driver is needed for use with a mouse or keyboard, on a Mac or PC.

Jeff wrote:

since the Griffin driver is compatible with OS 10.3.9 or earlier.

I have a Griffin iMate that lets me continue to use my ancient and wonderful Apple ADB "Nimitz" keyboard (M3501) from the mid-1990s on my newer Macs. It is best to use NO drivers--I got KPs when I installed the drivers. Turns out the drivers are only needed if you plan to use an ADB graphics tablet.

Once I moved past 10.3.9, I picked up some minor problems with the iMate and my keyboard, but I am so accustomed to the old board that I simply deal with the issues. The issues are:

1) The Caps Lock key function can get reversed; the light is off and the board type lower case, but the Caps Lock button is down.
2) Occasional wake from sleep issues. The board will send a bunch of space bar commands until you hit some other key. I find waking from sleep by clicking the mouse button seldom invokes this behavior.

Bottom line: I've used the iMate to connect ann ADB device to Macs running as high as 10.5.8. haven't tried on the MacBook Pro since upgrading to 10.6 but

Pages wrote:

I really like the click on the mouse and the retro-vintage feel it gives you when you use it.

I use modern two-button USB mice but find switching the primary key from left to right restores the way I used to hold the old single-button ADB mice and produces little hand strain.