liferay-ui:icon target=_blank of liferay6.0.5 not open link page in new tab

If set parameter target to _blank of the following lefary tag:

<liferay-ui:icon image=""  label=""  target="_blank"  message=""  url=""/>

It just shows “Opens New Window” beside the link text but not open link page in new tab.

If you look source of taglib/ui/icon/page.jsp you will see

<aui:a href="<%= url %>" id="<%= id %>" lang="<%= lang %>" target="<%= target %>">

<%= linkContent %>

</aui:a>

It creates link using aui:a tag here I found if I remove id parameter it woks fine. I mean if I make it like bellow:

<aui:a href="<%= url %>" lang="<%= lang %>" target="<%= target %>">

<%= linkContent %>

</aui:a>

It opens link page in new tab if target parameter set to _blank of liferay-ui:icon otherwise it opens on same window though target parameter is set to _blank.