Y2K Type Troubles Created by New OS X Version Number

Via Risk Digest -

Mac OS X 10.4.10 is the first iterative release of Mac OS X to have 5 digits in its version string (1, 0, 4, 1, 0).

It is also the first iterative release of Mac OS X to use the ".10" extension. This is causing some significant issues.

The initial three [sic] digits for "10.4.10" are the same as "10.4.1," an earlier release of Mac OS X 10.4 (Tiger).

Since the "MAC_OS_X_VERSION_ACTUAL" string (used by Cocoa applications to determine the current OS version) can carry a maximum of four digits, Mac OS X 10.4.10 and and 10.4.1 are both labeled "1041." This means that some applications recognize Mac OS X 10.4.10's version string as Mac OS X 10.4.1 and refuse to properly run, erroneously thinking that the system version is too old.

For instance, the application UNO requires Mac OS X 10.4.4. When running under Mac OS X 10.4.10, it recognizes the Mac OS X version number as 10.4.1 and refuses to operate.

Essentially, the built-in Cocoa method for forbidding an app to run on too low a system breaks against Mac OS X 10.4.10.