Evaluating expression of Facelets components in Richfaces sort

I have some problem evaluating expression in a Facelets component defined in a .taglib.xml

SortField2.getExpression() 

gives me the value "#{sortBy}" instead of evaluating the value.

My component (a simple column) is defined as:

  <ui:composition>
      <rich:column sortBy="#{sortBy}" width=开发者_JS百科"#{width}" styleClass="#{styleClass}">
          <f:facet name="header">#{header}</f:facet>
          <ui:insert />
      </rich:column>
  </ui:composition>

I see that in TagValueExpression there is a "original" field which contains my value, but unfortunately it is private.

Any idea on how to extract it?

Also posted on Richfaces Forum

Thank you for your help.

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You may be able to get "sortExpression" to work, instead of using "sortBy".

Also, instead of #{sortBy}, would ${sortBy} do any good? (A long shot)