Earlier quoted context omitted.
http://www.unicode.org/versions/Unicode6.2.0/ch08.pdf page 250 Screenshot of relevant text: http://i.imgur.com/xMnHDg4.png Basically certain Hebrew characters have descenders which can overlap with diatric marks in the next line of text. These variations are suitable replacements that alter it slightly so it won't overlap.
I'd so prefer to see #define HEBREW_CHAR_MIN 0xfb20 #define HEBREW_CHAR_MAX 0xfb4f (Probably with even more descriptive names, but I don't know the problem domain.)
enum { HebrewCharMin=0xfb20, HebrewCharMax=0xfb4f, };