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<DIV><FONT face="Bookman Old Style">Hi,</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">I suggest you start from the
filter->Update() to debug into it to see which method is called.</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">Cheers,</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">Yixun Liu</FONT></DIV></BODY></HTML>