Same driver in 1.5.8 as 1.5.9, the code working around the driver in 1.5.8 is ok, still problems though, as you can read in the gargoyle forum, so its not totally in the clear, but 1.5.9 was supposed to 'fix' those problems, but all the while created new problems. So here we are now. :)
Also for the record, since gargoyle is openwrt based, you'd do good to keep track of openwrt's svn timeline to see when the issue will be fixed, with dd-wrt, you can't see what changes are being made to its ath9k driver because changes are made in a non-public tree, so you can't see it, but basically when openwrt's ath9k gets worked on, dd-wrt's ath9k driver does as well.