Added note about possible IE 6.0 problems

git-svn-id: https://flot.googlecode.com/svn/trunk@31 1e0a6537-2640-0410-bfb7-f154510ff394

README.txt

@@ -23,6 +23,11 @@ include the excanvas script like this:
 
   <!--[if IE]><script language="javascript" type="text/javascript" src="excanvas.js"></script><![endif]-->
 
+If it's not working on your development IE 6.0, check that it has
+support for VML which excanvas is relying on. It appears that some
+stripped down versions used for test environments on virtual machines
+lack the VML support.
+  
 Also note that you need at least jQuery 1.2.1.