Remove %20 characters from hyperlink

This is the code that creates a hyperlinkfield:
            <asp:hyperlinkfield
                Headertext="Property ID"
                datatextfield="cpnyid"
                datanavigateurlfields="cpnyid"
                datanavigateurlformatstring="{0}.aspx" />
 
The resulting html created is:
<td><a href="CAPRI%20%20%20%20%20.aspx">CAPRI & ...