severe problems with 2.8.18. and 2.8.19 using the "new" wireless package and Atheros 5213 chipsets on 802.11g.
To give you an impression: On point-to-point links just about 600 meters apart using 14 dBi directional antennas and a signal level of about -42 dBm I had ping times up to 600 ms on an unused link. The max. throughput I could get over the links was about 500 kB/s.
The CCQ (client connection quality) was around 3 to 20, which I read as very bad.
i have very similar problems on an accesspoint (about 25 clients, 2.8.19, 802.11g, atheros mini-pci-cards).
and even worse: after switching to 2.8.19 wireless-legacy only clients with atheros wlan-cards can connect, no other (e.g. prism)
we informed support too, but haven't got an answer to this problem.
at the moment mt is therefore unusable as access-point for 802.11g. we are going to try 802.11b now, but i'am not happy with this situation.
any ideas, hints?