The maintainer, Jean Tourrilhes <jt.com>, says:
"The latest beta work well enough, it's shipped with Debian Squeeze."

It was released on Nov-2009, and stable enough since then.

 wireless 30 :
 -----------
		(Suggested by Johannes Berg <johannes>)
	o Display non-ASCII char in ESSID using escape sequence [iwlib]
	o Allow input of non-ASCII char in ESSID using escape sequence [iwlib]
	---
	o Fix probing to not probe wildcards (left over '%d'->'*') [ifrename]
	o Output number of mapping matched (display + exit status) [ifrename]
		(Bug reported by Ben Hutchings)
	o Don't load mapping file if using options '-n' + '-i' [ifrename]
	---
	o When using takeover, redo probing in case eth0 was in use [ifrename]
	o Update Hotplug documentation, add uDev bits [HOTPLUG-UDEV.txt]
	o Add ESSID bug patches and documentation [ESSID-BUG.txt]
	o Make wireless.21.h LGPL as promised a long time ago [wireless.21.h]
	---
		(Bug reported by Shaddy Baddah)
	o Fix unaligned access on SPARC in the 64->32 bit workaround [iwlib.c]
	---
		(From Maxime Charpenne <maxime.charpenne>)
	o Mise à jour de la traduction en francais des pages manuel [fr/*]
	---
	o Use wireless.22.h, make it LGPL [iwlib.h/wireless.22.h]
	o Show Scanning Capabilities in "iwlist event" [iwlist]
		(Bug reported by Nikita Zhernosenko)
	o Fix parsing of retry/power when modifier is used [iwconfig]
		(Bug reported by Alexis Phoenix)
	o Remove trailing '/' in INSTALL_* that fooled checkinstall [Makefile]
		(From Dan Williams <dcbw>)
	o Scan capabilities in struct iw_range [wireless.h]
		(From Guus Sliepen <guus>)
	o Install localised man page [Makefile]
	---
	o Fix #define that broke 32->64 bit workaround [wireless.22.h]
	o Workaround kernel bug when getting ESSID [iwlib/iwconfig/iwgetid]
		(From Gerald Pfeifer  <gerald>)
	o Fix gramar in man page, add about hidden networks [iwlist.8]
	---
		(From Reinette Chatre <reinette.chatre>)
	o Enable scan buffer to grow up to 65535 instead of 32768 [iwlist]
	o Return a proper error if scan result exceed buffer max [iwlist]
		(From Jean Tourrilhes)
	o Do above two fixes for the simple scan API [iwlib]
		(From Claudio Ferronato <claiudio>)
	o Spelling and typos in [iwconfig.8]
	---
	o Create iwlib-private.h to minimise namespace pollution [iwlib]
	o More fix to the 64->32bit band-aid for encode [iwlib]
	o Update udev rule to remove a warning [19-udev-ifrename.rules]
		(from Ritesh Raj Sarraf <rrs> and Guus Sliepen)
	o Propagate error codes out of main for get [iwconfig/iwlist/iwspy]
		(From Guus Sliepen <guus>)
	o Remove spurious commands from Czech iwconfig manpage.