Convert labels to annotation - Engine

[AlessandroValra]

Hi all, I'm trying to convert labels to annotation in arcgis engine's project with ConvertLabelsToAnnotation class as shown to link

http://help.arcgis.com/en/sdk/10.0/arcobjects_net/conceptualhelp/index.html#/Converting_labels_to_ge...

I read that Feature-linked annotation can only be created with an ArcEditor or higher license level.
I've ArcMap installed on my pc and an ArcInfo's license.
Why it doesn't work in arcgis engine although I have a "valid" license?

Can someone help me?
TIA

Alder