Strange behaviour of Jena in OSGi Blueprint

Everytime I do a:
model.read(input, null);
I get:

com.hp.hpl.jena.shared.ConfigException: Reader not found on classpath
at com.hp.hpl.jena.rdf.model.impl.RDFReaderFImpl.getReader(RDFReaderFImpl.java:108)
ClassNotFoundException: org.apache.jena.riot.adapters.JenaReadersWriters$RDFReaderRIOT_RDFXML

I'm working in an OSGi blueprint environment. When I test this in a normal environment, everything works ok.

My source code is:

final String modelText = "\n"
+ "<rdf:RDF \n"
+ " xmlns:res=\"http://www.w3.org/2005/sparql-results#\" xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"> \n"
+ " <rdf:Description rdf:about=\"http://www.w3.org/2005/sparql-results#ResultSet\">\n"
+ " <res:solution rdf:nodeID=\"r0\"/>\n"
+ " <res:solution rdf:nodeID=\"r1\"/>\n"
+ " <res:solution rdf:nodeID=\"r2\"/>\n"
+ " </rdf:Description>\n" + "</rdf:RDF>";
final Model model = ModelFactory.createDefaultModel();
model.read(new ByteArrayInputStream(modelText.getBytes()), null);
model.close();

I also add this in my pom, but it seems to do nothing:

<!-- jena bundle can run stand along without ARQ. However if
ARQ is present then it can call RDFReaderF to specify that various RIOT
readers should be used instead of the ones in the jena bundle. The jena bundle
therefore needs access to the RIOT classes. So define an optional dependency
from the jena bundle to the arq bundle. This allows RDFReaderF to load the
RIOT parser classes. -->
<Require-Bundle>
wrap_mvn_org.apache.jena_jena-arq_2.11.1-SNAPSHOT;resolution:=optional
</Require-Bundle>