Recently in the Apple Discussions a user had some problems making Hebrew Final Kaf plus Sheva display correctly. Getting this right requires that the font have enough smarts to combine the two characters involved (U+05DA and U+05B0) properly, putting the Sheva inside the Final Kaf instead of just underneath its vertical stroke, as is done elsewhere. Apple's Hebrew Qwerty keyboard layout also requires that you type Shift + k to get Final Kaf rather than just Kaf. This graphic shows how different Hebrew fonts I have on my Leopard system render it in TextEdit. Unfortunately 4 of the 5 supplied by Apple don't do a good job.