[Ifeffit] Bug in Athena?

[Zajac, Dariusz A.]

Dear Bruce, Dear All,
maybe it is a naïve question but I want to ask and to point this problem...

Windows XP. Athena 0.8.059
Sc.Linux. Athena 0.8.060

I have a set of data with refernces  (one sample, many scans). I have marked sample's groups and do "merge marked data in mu(E)" then I get merged data together with reference (2 groups: merge - sample, and Ref merge - reference). 
But...
...if I have marked reference sample's groups and do "merge" then I get 2 groups: merge - which is merged data of reference, and Ref merge - which is marged data of sample. Oposite to that I did in first example!

Is any hidden idea, I can not see, why it should be that way? If you don't know about that, can confuse and surprise...
cheers
darek