I've always been bothered by what has seemed to me to be an almost supersitious need to tack on "in Christ's name" at the end of prayers as if were some sort of incantation. It is eroneous to believe that we are required to do this as Christians so that in an interfaith setting we feel we must impose certain language on non-Christians. The following expresses my views on this subject wonderfully:
Many people have a very strangely childish notion, that "praying in the name of Christ" means simply the addition of the words "through Jesus Christ our Lord" at the end of their prayers. But depend upon it, they do not by adding these words, or any words, bring it about that their prayers should be in the name of Christ. To pray in the name of Christ means to pray in such a way as represents Christ. The representative always must speak in the spirit and meaning of those for whom he speaks. If Christ is our representative, that must be because He speaks our wishes, or what we ought to make our wishes; and if we are to pray in the name of Christ, that means that we are, however far off, expressing His wishes and intentions.
-- Charles Gore