Using SVN 353 on Gentoo Linux x86_64, I see the following behavior: When moving on certain parts of the map uphill in an approximate 45° angle on terrain, the movement jerks periodically (i.e. the player is moving up and down and moves sideways downhill sometimes). The exact phaenomenon differs from time to time.
This can be reproduced with the attached map. If one spawns in that map using DeathMatch and walks straight up for about 8 seconds, then turns around 180° there will be a hill up left which has a black texture. Walking towards that black texture always shows the described effect.