1.6.1 Carpet bug

Hello mojang team, First off i need to thank you guys for this lovely game.
I was trying the 1.6.1 pre-release Update And i found this bug .
When you run on Any carpet , you can see some dirt flying next to your character. Its like you're running on dirt or something.
I believe this is a bug , because it's not really that realistic
I uploaded a picture of the problem if you don't get my point.
Thanks for reading.
Lick_the_Cat