UTC, local timeMode options is not applied.

[kibumh]

no mode argument for Month and FullYear. (default value 'UTC' is applied)
This results in 2012/5/1 to be a next day of 2012/5/31 in some timezone.

$ git diff
diff --git a/js/Date.js b/js/Date.js
index b380511..bd32d3d 100644
--- a/js/Date.js
+++ b/js/Date.js
@@ -30,8 +30,8 @@ Flotr.Date = {
         S: leftPad(get(d, 'Seconds', mode)),
         s: get(d, 'Milliseconds', mode),
         d: get(d, 'Date', mode).toString(),
-        m: (get(d, 'Month') + 1).toString(),
-        y: get(d, 'FullYear').toString(),
+        m: (get(d, 'Month', mode) + 1).toString(),
+        y: get(d, 'FullYear', mode).toString(),
         b: Flotr.Date.monthNames[get(d, 'Month', mode)]
       };

[cesutherland]

looks good, could you attach it as a pull request?