ASP.Net Membership saves changed password as plain text even with Hashed passwordFormat set

Hi all, I'm using the ASP.Net SqlMembershipProvider to manage my users. Here is my config:
<membership defaultProvider="SqlProvider" userIsOnlineTimeWindow="15">
                <providers>
                        <clear />
                        <add
                                name="SqlProvider"
                                type="System.Web.Security.SqlMembershipProvider, System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"
                          &nbs ...