System.ArgumentExceptions on startup of WPF application

Question

We've created a custom theme for a WPF application. The styles in this theme use various bindings. On startup of the application a lot of Exceptions like this occur:

System.ArgumentException occurred, Message="The requested value \"RecordFixToBottomPrompt\" could not be found.", Source="mscorlib", at StackTrace: bei System.Enum.Parse(Type enumType, String value, Boolean ignoreCase)

These exceptions seem to be caused by bindings in our theme, i.e.:

Setter Property="FixToBottomPrompt" Value="{Binding Path=Value, Source={x:Static igDP:Resources.RecordFixToBottomPrompt}}"/>

However, when the application is running the bindings are working fine.

Does anyone know what can cause this behaviour?

Thanks!