Not able to open FBA Role Management-Site

hi there,

i'm having a Problem when trying to open the "FBA Role Management"-Site via Site Settings.

I'm getting an the following exception:
"The configured Role Provider (WindowsTokenRoleProvider) relies upon Windows authentication to determine the groups that the user is allowed to be a member of. ASP.NET Role Manager cannot be used to manage Windows users and groups. Please use the SQLRoleProvider if you would like to support custom user/role assignment."

Any Idea how to fix this?

Here's the Code of the web.config of the specific site collection:
    <roleManager enabled="true" cacheRolesInCookie="false" cookieName=".ASPXROLES" cookieTimeout="30" cookiePath="/" cookieRequireSSL="false" cookieSlidingExpiration="true" cookieProtection="All" defaultProvider="c" createPersistentCookie="false" maxCachedResults="25">
      <providers>
        <clear />
        <add connectionStringName="AspNetSqlMemberShipProvider" applicationName="/" name="AspNetSqlRoleProvider" type="System.Web.Security.SqlRoleProvider, System.Web, Version=2.0.0.0, &#xD;&#xA;Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
        <add applicationName="/" name="SqlRole" type="System.Web.Security.WindowsTokenRoleProvider, System.Web, Version=2.0.0.0, &#xD;&#xA;Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
        <add name="c" type="Microsoft.SharePoint.Administration.Claims.SPClaimsAuthRoleProvider, &#xD;&#xA;Microsoft.SharePoint, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" />
      </providers>
    </roleManager>
In your web application settings in Central Admin, I believe you have the role provider set to 'SqlRole' - which is a WindowsTokenRoleProvider and not supported. You would have to set it to 'AspNetSqlMemberShipProvider' which is a SqlRoleProvider and is supported.