Not having Hebrew on my BB i searched the RIM site for info. aparently there is a display issue sometimes. they do not indicate time /date display issues but based on the reading it may be connected.
Not exactly your issue but close. Read the link. Also make sure the phone is set to display network time and not manual.
KB25037-Contents of email messages sent from the BlackBerry smartphone are inverted or scrambled in various email applications when the message contains Hebrew characters 0 1888836636