Uppercase tag names in XML output

Question

For a project I once created a web service which generates xml files, for each xml file I created a class, like this:

public class Tsjoeketjoek
{
    [XmlAttribute]
    public string Num;

    [XmlAttribute]
    public string Type;

    [XmlAttribute]
    public string Car;

    [XmlAttribute]
    public string Deel;

    [XmlAttribute]
    public string Resa;

    [XmlAttribute]
    public string Prest;

    public FootNote FootNote;

    public List<Station> Rit;
}

 For comptability reasons the tag names need to be uppercase. 

 

Now I know I can enforce the tagnames in the code itself, by actually naming each field, I am wondering if there is no better method. There a lot of classes I would have to do this manual change for..

 

For example, can't I write an extension for XmlSerializer so I can enforce uppercase tagnames that way?