Thorny Dragon spazzing out

My girlfriend and I play on a dedicated unofficial Ragnarok server, last night she mentioned that her Thorny Dragon was acting weird so I glanced over at her screen.

Her Thorny Dragon was not on wander, and was set to passive, but was running around on her little island home as if it was chasing something down (but nothing was there). I had her whistle it to follow and it complied until it reached her, then ran off a bit, then returned. When she had it stop following, it resumed running around like a crazy animal, running approximately 50ft then changing directions.

Popped on for a bit this morning and saw her Thorny Dragon darting across her island once more. I hopped on it and tried parking it only to have it run off again the moment I dismounted.

Doing a quick search, it seems to have happened to others in the past with random dinos but I couldn't find any sort of fix for this. Has anyone else heard of this or had it happen?