regexp RE.subst() issue

  
Hello,
I am using the RE.subst method.Here is the code on one of my JSP pages.this
is very similar to the example in the docs of the RE
<%
RE r = new RE("( http://[\\.\\w\\-\\?/~_@ <http://[///w//-//?/~_@&=%>
&=%]+)");
String toSubsWith="<a href=\"$0\">$0</a>";
 
String tempBefStr=r.subst(strDescription,toSubsWith);
%>

strDescription has in it http://something <http://something/>  .WHat is
happening is it is finding the http:  but while substituting it is
substituting the $0 instead of the whole match.

For example if strDescription =Welcome to http:/www.yahoo.com isnt it great
The string getting returned is "Welcome to $0 isnt it great"

I have tried using 

String toSubsWith="<a href=\"$&\">$&</a>";

but that dint help.Am I missing something?I am using the
jakarta-regexp-1.3.jar 

 

Thanks AP