internet explorer 9 - Vaadin shows "Message: Object doesn't support this property or method" with IE9 -

whenever compile widgetset vaadin 6.5.6 or 6.5.7 in eclipse , run application works in firefox , safari. ie gives :

webpage error details  user agent: mozilla/4.0 (compatible; msie 8.0; windows nt 6.1; wow64; trident/4.0; slcc2; .net clr 2.0.50727; .net clr 3.5.30729; .net clr 3.0.30729; media center pc 6.0; .net4.0c) timestamp: fri, 29 apr 2011 16:45:28 utc   message: object doesn't support property or method line: 2860 char: 445 code: 0 uri: http://127.0.0.1:8080/vaadin/widgetsets/com.example.newvaadin9.widgetset.newvaadin9widgetset/6f6ce40261565705783015cf405e65e8.cache.html 

:upon loading. know why?

support ie9 added vaadin 6.6. pre-release released yesterday final targeted released in 2 weeks. please upgrade.