Twitter search: how do I include spaces before and after search string? (hint: %20 doesn't work!)

I want to search tweets which contain a standalone string "$T", for instance:

$T is doing well today!
I can't wait to catch my flight with $T
If $t is down, I am happy

But I do not want results that include $T as part of a larger string, for instance

My mother said $ttttttt so I shut up Making money fa$t!!

For this, I tried 3 different search queries, with 2 of them encoding spaces before and after the string:

http://search.twitt开发者_如何学Pythoner.com/search.json?q=%24T
http://search.twitter.com/search.json?q=+%24T+
http://search.twitter.com/search.json?q=%20%24T%20

But all of this doesn't help. What should be the correct query or do I just have to filter the results?

Did you try quotation marks and/or plus signs in your search, like the web based search interface does?