Anti-virus don’t like each other?

I’ve been using free AVG for quite a while now and decided to try some other free anti-virus available out in the market. After an uneventful scheduled weekly scan by AVG which only picked out the usual bunch of website cookies, I installed Avira AntiVir. Once the software is updated, I ran a complete system scan.

I picked out a few trojans which AVG missed but the strangest occurrence has to be the following:

avira avg

I don’t quite understand what’s happening but it seems AVG’s Resident Shield picked out a trojan scanned by Avira or somehow it just labelled Avira’s avscan a trojan.