Webmail User Guide
Regional Settings
Options > General > Regional Settings

Field Explanation
Character Set Allows different languages and language character's to be sent in an email.  To change the Character set, select the drop down arrow to select the desired language setting. This is set to UTF-8 as default which is a universal character setting supporting all languages. 
Time zone This setting is used in message headers to correctly display local times of email sent and received.  To change the Time Zone, select the drop down arrow and select the desired time zone setting which should match your current timezone. Using a correct timezone is important if calendaring is enabled, in order to place appointments into the correct timezone.