{{Quickfixn}} How best to deal with multiple FIX versions

[xmoon 2000]

I connect to several APIs that all use FXI4.2 but now I wish to
connect to another that uses its own version of FIX4.4.

I have an router app that send orders to the various APIs and it would
appear that I need to duplicate all my methods (e.g. the OnMessage(),
NewSingleOrder etc) to cope with the 2 FIX protocols.

Is there a smarter way to do this to avoid this duplication?