Fail to invoke Java API of RTC in osgi bundles, need help

I am developing an application which invokes Java API of RTC. When the application runs in stand-alone J2SE, everything is fine.
However when the application runs in the osgi bundles, exception occurs.
Is there any limitation with invoking the Java API of RTC.

The error stack:
java.lang.IllegalArgumentException: The type name Contributor and the namespace URI com.ibm.team.repository do not resolve to an IItemType.
at com.ibm.team.repository.common.internal.querypath.AbstractQueryPathModel$Implementation.getItemType(AbstractQueryPathModel.java:190)
at com.ibm.team.repository.common.query.IQuery$Factory.newInstance(IQuery.java:92)
at com.ibm.team.repository.client.internal.ContributorManager.createAllContributorsQuery(ContributorManager.java:57)
at com.ibm.team.repository.client.internal.ContributorManager.<clinit>(ContributorManager.java:45)
at java.lang.J9VMInternals.initializeImpl(Native Method)
at java.lang.J9VMInternals.initialize(J9VMInternals.java:200)
at com.ibm.team.repository.client.internal.TeamRepository.<init>(TeamRepository.java:387)
at com.ibm.team.repository.client.internal.TeamRepositoryService.createSharedTeamRepository(TeamRepositoryService.java:366)
at com.ibm.team.repository.client.internal.TeamRepositoryService.getTeamRepository(TeamRepositoryService.java:91)
at com.ibm.team.repository.client.internal.TeamRepositoryService.getTeamRepository(TeamRepositoryService.java:110)