Why does the Sony Log and Transfer Plugin for Final Cut Pro fail to install on my OS X 10.6.8 imac running Final Cut Pro 7.0.3?

I acquire MPEG 4 footage with a SONY EX3 camera.

I wish to edit the footage with the Final Cut Pro 7 on my iMac, so I went to SONY's site and downloaded the XDCAM EX Log and Transfer Plugin (PDZK-LT1).

I am running OS X version 10.6.8 on a 3.2 GHz Intel Core i3 iMac, and I have Final Cut Pro 7.0.3 installed.

When I try to install the Plugin on my System Drive, however, the "Select a Destination" window states "Sony XDCAM EX Log and Transfer Plug-in can't be installed on this disk. Final Cut Pro 6.0.3 or higher is recommended for this software."

FCP 7.0.3 IS higher than 6.0.3, so why does the Sony Log and Transfer Plug-in not install on my system?

(Is there a newer version of the plugin than the version 1.2 I am trying to install? There doesn't seem to be.)

I am running 7.0.3 on 10.6.8 - the latest version I have of XDCAM Transfer is 2.12.0 which works fine.