I don't know why. Perhaps it was a gesture of good will in order to avoid any future conflicts with the Vatican. We can't afford having Catholics against us. Not anymore. I am anti-ecumenism but I don't support giving people the finger either. Serbs have good to be more pragmatic and think more in the long-run. Most of the decisions made by our leaders in history have been to our detriment.
No my friend Putin is a Vatican puppet, I love russian people but this is a true. Let me ask you one question did some serbian ruler (except Tito - but he was not our true leader) ever visit a pope? No until came Boris Tadic !
The similar thing is with russians!
In Serbia Pope's feet never step in ! Now, he is invited, by Irinej, to came down in Nis on ecumenic Council 2013 . For that event ,in the Nis ,under construction is huge Catholic cross! And monitoring is done Archbishop Stanislav Hocevar !