Pending BW Queues in SMQ1 with NOSEND status since long

HI All,

There are pending Queues in SMQ1 for BW in SAP CRM Productionsystem with NOSEND status for almost 3 months and they are not getting cleared even after extracting all the data for the datasources showing in SMQ1. But there BDOCS in these are from Nov 2013 to till yesterday.

So my question is :

1. How can i check whether to delete these queues or not?

2. How can we avoid these pending queues moving further?

Please suggest.

Thanks,

Javed