jQuery Forum

This technique doesn’t work in ie6 as is, mainly because ie6 doesn’t allow transparent borders, but there is a fix for that. What you need to do is give the “transparent” sides a completely different color like pink and then use filter: chroma to turn that color transparent.

1.  /* IE6 */
   .chat-bubble-arrow {
       _border-left-color: pink;
       _border-bottom-color: pink;
       _border-right-color: pink;
       _filter: chroma(color=pink);
   }