fieldmetadata of greek database not showing right

I have a greek database in sql server 2008 with the character columns set to nvarchar.When i connect to the database from php i have set Characterset to UTF-8 and in the header of the html files charset="utf-8".When i retrieve data from the database it shows fine in the browser,but if i want to retrieve the column names with sqlsrv_field_metadata(), the name fields are shown with question marks.

If i retrieve the column names from the infromation_schema.columns view they are shown fine.

What can i do to get the column names from the sqlsrv_field_metadata()?