non-spacing diacritics cannot be entered by keyboard
Operating system version
Mac OS 10.6.5
Description of the issue
I am unable to enter non-spacing diacritic characters into any field using the keyboard.
Steps to reproduce the problem
I want to add (for example) a non-spacing diacritic acute accent (unicode 0301) using the keyboard (I have a keyboard which will do this with a keystroke: but the problem will recur on any keyboard, whether provided with the Mac OS or not, e.g. Arabic QWERTY for Arabic non-spacing vowel diacritics). So, for example, switch to Arabic QWERTY keyboard. Type "k" and get Arabic "k". Then try to type non-spacing vowel "a" (keystroke: option-a).
Expected result is that the non-spacing diacritic should appear in the text field. It could be misplaced, as it would be most likely in Microsoft Word, but it should still appear somewhere.
Warning beep/chime from OS occurs. No character is entered into text field.
The non-spacing diacritics can be entered by dragging them from the Macintosh Character Viewer palette into the text field. They cannot be entered by pressing "insert" from the Character Viewer Palette or by double-clicking the diacritic in the Character Viewer Palette.
Text can also be copied and pasted in from another application. But font switches may occur (see http://forums.filemaker.com/posts/fc46d59729 for discussion and work-around: not pretty).
This is a big hassle. Please help.