Hint: Make sure to use UTF-8 as input encoding for all transferred data. Otherwise the chance for misinterpreted characters is given.

The Maileon API supports the following standard contact fields (note that the email address and the external id of the contact have their own tags in XML documents):

Field Remark
ADDRESS The length must not exceed 255 characters.
BIRTHDAY Allowed patterns: yyyy-MM-dd and yyyy-MM-dd HH:mm:ss
CITY The length must not exceed 255 characters.
COUNTRY The length must not exceed 255 characters.
FIRSTNAME The length must not exceed 255 characters.
GENDER Allowed values: m (male) and f (female)
HNR The length must not exceed 255 characters.
LASTNAME The length must not exceed 255 characters.
FULLNAME The length must not exceed 255 characters.
LOCALE The value must follow the pattern: xx (example: en) or xx_XX (example: de_DE). „xx" is the two character language code (ISO 639) and „XX" the two character code for the country of the language (ISO 3166). Example: british english is notated as „en_GB" and american english as „en_US". For just marking a contact as english speaking „en" is usually enough.
NAMEDAY Allowed patterns: yyyy-mm-dd and yyyy-mm-dd hh:mm:ss
ORGANIZATION The length must not exceed 255 characters.
REGION The length must not exceed 255 characters.
STATE The length must not exceed 255 characters.
SALUTATION The length must not exceed 255 characters.
TITLE The length must not exceed 255 characters.
ZIP The length must not exceed 255 characters.