Parse error when using elements.less

I’m using Less Elements

and I get this error:

#BW LESS-CSS: lessc fatal error
parse error: failed at <code>filter: e(%("progid:DXImageTransform.Microsoft.gradient(startColorstr='%d', endColorstr='%d', GradientType=0)",@stop,@start));</code> .../wordpress-3.4.2/apps/wordpress/htdocs/wp-content/themes/aos/elements.less on line 23

http://ww.wp.xz.cn/extend/plugins/bw-less-css/