WPF TargetType is ignored

[=?ISO-8859-1?Q?Norbert_P=FCrringer?=]

Hello there,

I've got following style defined:

<Style TargetType="{x: Type GridViewColumn} ">
<Setter Property="Heade r" Value="Test" />
<Setter Property="CellT emplate" Value="{StaticR esource
CellTemplate_Na me}" />
</Style>

This style definition is ignored, if a GridViewColumn is defined. Why?
Is there only a certain type of target types allowed?

Regards,
Norbert