We use Openfire 3.9.3. Its MySql database uses utf8_persian_ci collation and in openfire.xml we have:
...<defaultProvider>
<driver>com.mysql.jdbc.Driver</driver>
<serverURL>jdbc:mysql://localhost:3306/openfire?useUnicode=true&amp;characterEncoding=UTF-8</serverURL>
<mysql>
<useUnicode>true</useUnicode>
</mysql> ....
The problem is that offline messages which contain Persian characters (UTF-8 encoded) are saved as strings of question marks. For example سلام (means hello in Persian) is stored and showed like ????.
MySQL does not have proper Unicode support, which makes supporting data in non-Western languages difficult. However, the MySQL JDBC driver has a workaround which can be enabled by adding
to the URL of the JDBC driver. You can edit the conf/openfire.xml file to add this value.
Note: If the mechanism you use to configure a JDBC URL is XML-based, you will need to use the XML character literal & to separate configuration parameters, as the ampersand is a reserved character for XML.
Also be sure that your DB and tables have utf8 encoding.