tube-stream: fix a crasher when disposing a not accepted tube
tube-stream: fix a crasher when disposing a not accepted tube


20071007162740-7fe3f-688887358307bce75f6293fdf34ada2c87dc23b0.gz

mlundblad/telepathy-gabble,mlundblad/telepathy-gabble,jku/telepathy-gabble,community-ssu/telepathy-gabble,community-ssu/telepathy-gabble,Ziemin/telepathy-gabble,Ziemin/telepathy-gabble,Ziemin/telepathy-gabble,mlundblad/telepathy-gabble,community-ssu/telepathy-gabble,community-ssu/telepathy-gabble,jku/telepathy-gabble,Ziemin/telepathy-gabble,jku/telepathy-gabble