Inline Function Call Not working

Can someone tell me what is wrong here? The MultipleSystems function doesn't seem to be getting called. Am I doing this right?

Thanks!

Code:

---

<asp:Label id="lblName" runat="server" text = '<%# MultipleSystems("123-12-1234", "321-21-4321") %>'></asp:Label></TD>

---

VB Code:

Public Function MultipleSystems(ByVal mainsystempn As String, ByVal addsystempn As String) As String
        If chkOtherOptions1.Checked = True Then
            Return mainsystempn + "/" + addsystempn
        Else
            Return mainsystempn
        End If
    End Function

Maybe that should be <% =MultipleSystem.... %> instead?

Why not just assign lblName.Text = MultipleSystem(...) in your code?