Embedded font using flash.text.engine works on AIR2.6 but no AIR2.5

I use the following embed statement:

[Embed(source = "C:\\Windows\\fonts\\Kids_Plain.ttf", fontFamily = "Kids", embedAsCFF="true")]

private var Kids:Class;

...

...

I use flash.text.engine class functions and the program runs fine on AIR2.6 on Android, but the text does not show on AIR2.5.  According to the Adobe documentation, the flash.text.engine class should work on the AIR2.5 platform.  Or is there something wrong with the way I embed the font?

Anyone know what the problem is?

Thanks in advance!