А) откатить text.dm до исходного
Б) заменить repl_chars в sanitize_simple с list("\n"="#","\t"="#","�"="�") на list("я"="ÿ", "\n"="#","\t"="#","�"="�")
В) Заменой заменить все html_decode на rhtml_decode, а html_encode на rhtml_encode
Г)Добавить этот код:
/proc/rhtml_encode(var/msg)
	var/list/c = text2list(msg, "я")
	if(c.len == 1)
		c = text2list(msg, "ÿ")
		if(c.len == 1)
			return html_encode(msg)
	var/out = ""
	var/first = 1
	for(var/text in c)
		if(!first)
			out += "ÿ"
		first = 0
		out += html_encode(text)
	return out

/proc/rhtml_decode(var/msg)
	var/list/c = text2list(msg, "я")
	if(c.len == 1)
		c = text2list(msg, "ÿ")
		if(c.len == 1)
			return html_decode(msg)
	var/out = ""
	var/first = 1
	for(var/text in c)
		if(!first)
			out += "ÿ"
		first = 0
		out += html_decode(text)
	return out

/proc/sanitize_ya(var/t)
	return sanitize_simple(t, list("я"="ÿ"))