Finding Flowdirection in Silverlight 4.0

Is there any way to find the flow direction of current culture in Silverlight 4.0. I know its possible in full .net with CultureInfo.TextInfo.IsRightToLeft, but since Silverlight has a cut down form of CLR and the internal 开发者_StackOverflow社区implementation of IsRightToLeft in .Net uses COM, this property is not available in Silverlight version of CLR.

Any suggestions of setting an extension method?

I know to provide checking the culture name and set the direction as right to left only for say hebrew, arabic etc. Is this the only way???

Thanks