accually yes you can, but it matters waht zone you are in or were in.... today 12-28-08 i went on and found this on the FRONT PAGE -
SMS Payment Options19-Dec-2008
Today, we’ve launched the SMS payment option for players from Denmark, Finland, Ireland, Norway and Sweden, which can be used to pay for a RuneScape membership. Read more...
so go on front page and if you are lucky and in that dang zoe maybe oyu can get a member ship!
runescape.com - front page