Persons having claims against the petitioner may be joined as parties and required to interplead when their claims are such that the petitioner is or may be exposed to double or multiple liability. It is not ground for objection to the joinder that the claim of the several claimants or the titles on which their claims depend do not have common origin or are not identical but are adverse to and independent of one another, or it is alleged that the petitioner is not liable in whole or in part to any or all of the claimants. A party exposed to similar liability may obtain such interpleader by way of crossclaim or counterpetition. The provisions of this rule supplement and do not in any way limit the joinder of parties otherwise permitted.