I just came across something extremely annoying that took me ages to figure out. I was calling window.open('http://www.twitter.com/share?url=...&text=...','twitterShare','width=500,height=400')
in a JS function for a SWF file to trigger and for the life of me the freakin' message wouldn't properly unencode hashtags and spaces (%23
and %20
respectively).
The solution is to REMOVE 'www.' from the twitter.com/share URL. Then it encodes everything fine.
I hope this helps someone so you don't muck around for an hour like I did.