Using OnClick event with PostBackUrl attribute of asp:Button

[Jbbrack03]

I have an asp:Button control like this;\[code\] <asp:Button ID="btnPayCC" CssClass="paymentButton" runat="server" Text="ONAYLA" OnClientClick="if(!doPostBack()) return false; frmMaster.target='_blank'" PostBackUrl="http://www.google.com" OnClick="btnPayCC_Click" />\[/code\]And doPostBack js function is;\[code\]function doPostBack() { __doPostBack('<%= btnPayCC.ClientID %>', ''); return true; };\[/code\]When I clicked the button, then it opens new page(google.com) as I wish, But do not postback into button control's OnClick event.What is the problem?How can I solve it?