Currently, ADE doesn't support valid ePub with RTL languages (such as Hebrew and Arabic). Actually, ADE doesn't even use the required (and available) system fonts, but this issue is being sorted by using embedded fonts in the ePub.
As a result, the text is being displayed from left to right and is not readable. Funny, but the text on the table of contents section is being displayed perfectly (right to left etc.).
While there are many applications (Calibre, AZARDI, Stanza, FBReader, EPUBReader for Firefox, Bookworm etc.) that handle's Hebrew ePub properly, this is a disapointment that ADE doesn't (attached is a sample of how it looks like...)
Does anybody know if this issue is planned to be sorted soon?