SPARQL DISTINCT

[Fabian Cretton]

Hi,
 
I thought DISTINCT was implemented, but it seems not ?
 
This query gives back all results with duplicates:
 
prefix qb: <http://purl.org/linked-data/cube#>
prefix sdmx-dimension: <http://purl.org/linked-data/sdmx/2009/dimension#>
SELECT DISTINCT ?year WHERE {
?obs a qb:Observation;
sdmx-dimension:timePeriod ?timeStamp.
BIND (SUBSTR(xsd:string(?timeStamp), 1, 4) AS ?year )
}
 
(On Sesame-OWLIM it works fine)
 
thanks for any advice
Fabian