It is often mistaken, but spraying is not only a sign of affection,I think in this situation it should be considered more as a property marking, which explains why he still chases his "friend".
(this is the comment I got from a behavioural therapist who studied at South Hampton and specialised in rabbits when I told her that one of my rabbits did this...on me... She sais, yes I could consider it a compliment, but also that the rabbit in question considered me as being his property)