testcase(cvsup'ed after ic_curchan changes):

	ifconfig ath0 mediaopt monitor channel 5 up
	ifconfig ath0 channel 9
	ifconfig ath0	# ath0 still sticks to channel 5

Index: ieee80211_ioctl.c
===================================================================
RCS file: /home/ncvs/src/sys/net80211/ieee80211_ioctl.c,v
retrieving revision 1.25
diff -u -p -u -p -r1.25 ieee80211_ioctl.c
--- ieee80211_ioctl.c	6 Jul 2005 15:38:27 -0000	1.25
+++ ieee80211_ioctl.c	22 Aug 2005 10:23:29 -0000
@@ -2039,7 +2039,7 @@ ieee80211_ioctl_set80211(struct ieee8021
 		    isclr(ic->ic_chan_active, ireq->i_val)) {
 			return EINVAL;
 		} else
-			ic->ic_ibss_chan = ic->ic_des_chan =
+			ic->ic_curchan = ic->ic_ibss_chan = ic->ic_des_chan =
 				&ic->ic_channels[ireq->i_val];
 		switch (ic->ic_state) {
 		case IEEE80211_S_INIT: