Best way to pass information between two message mappings

Hi,

I'm using two chained message mapppings (one after another in the operation mapping / interface mapping).

How could I pass information from the first message mapping (graphical or Java, I don't mind) to the next one without modifying the payload?

I'm thinking if it could be possible to set some custom header parameters in the header of the message, but I think that only works in adapter module development.

Thanks!