Different Versions of Reverse Invoke Server (RI) and interna

I would like to change our Installation from a Single Server Installation (SAP BC 4.0.1 = IS 4.0.1) to an environment where I use a Reverse Invoke szenario. Does anybody know whether it’s possible to use different IS versions for the RI Server and the internalserver ? In this special case I’d like to stay with 4.0.1 on the internal server but would use a 4.7 SAP BC (or if that’s not possible a 4.6) for the reverse invoke. The reason for this is that we’ve some third party addons installed and don’t get an information whether they will work with higher releases. On the other hand reverse invoke has some improvements in higher releases, so we 'd like to use these.
Does that make sense, or do you have any other recommodations ?