added special_use_attrib

lib/Connection.js

@@ -23,6 +23,7 @@ var MAX_INT = 9007199254740992,
       'ENVELOPE': 'envelope',
       'INTERNALDATE': 'date'
     },
+    SPECIAL_USE_ATTRIBUTES = ['\\All', '\\Archive', '\\Drafts', '\\Flagged', '\\Junk', '\\Sent', '\\Trash'],
     CRLF = '\r\n',
     RE_CMD = /^([^ ]+)(?: |$)/,
     RE_UIDCMD_HASRESULTS = /^UID (?:FETCH|SEARCH|SORT)/,
@@ -1233,6 +1234,10 @@ Connection.prototype._resUntagged = function(info) {
         parent: null
       };
 
+      for (var i = 0, len = SPECIAL_USE_ATTRIBUTES.length; i < len; ++i)
+        if (box['attribs'].indexOf(SPECIAL_USE_ATTRIBUTES[i]) > -1)
+          box['special_use_attrib'] = SPECIAL_USE_ATTRIBUTES[i];
+
       var name = info.text.name,
           curChildren = this._curReq.cbargs[0];