title: JDBCRealm doesn't work but there is no error message
body: <p>I hope that some one can help me. I try to configure the authentification via a JDBCRealm. It is the first time do this.</p>
  
  <p>Here are my Tables: </p>
  
  <pre><code>*Table userprincipal*
  email : varchar
  password : varchar
  
  *Table role*
  email : varchar
  role : varchar
  </code></pre>
  
  <p>I use a Tomcat 7 Server. So i changed the server.xml from</p>
  
  <pre><code>&lt;Realm className="org.apache.catalina.realm.LockOutRealm"&gt; 
      &lt;Realm className="org.apache.catalina.realm.UserDatabaseRealm"
             resourceName="UserDatabase"/&gt;
  &lt;/Realm&gt;
  </code></pre>
  
  <p>to (with correct login data)</p>
  
  <pre><code>&lt;Realm className="org.apache.catalina.realm.JDBCRealm"
          driverName="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://localhost:3306/myData"
          connectionName="user" 
          connectionPassword="pwd" 
          userTable="userprincipal"
          userNameCol="EMAIL" 
          userCredCol="password" 
          userRoleTable="userprincipal_role"
          roleNameCol="role" /&gt;
  </code></pre>
  
  <p>I added to the web.xml following lines</p>
  
  <pre><code>&lt;security-constraint&gt;
      &lt;web-resource-collection&gt;
          &lt;web-resource-name&gt;Default&lt;/web-resource-name&gt;
          &lt;url-pattern&gt;/services/customer/*&lt;/url-pattern&gt;
          &lt;url-pattern&gt;/services/material/loadAllByQuery&lt;/url-pattern&gt;
          &lt;url-pattern&gt;/services/SalesOrder/*&lt;/url-pattern&gt;
      &lt;/web-resource-collection&gt;
      &lt;auth-constraint&gt;
          &lt;role-name&gt;admin&lt;/role-name&gt;
          &lt;role-name&gt;user&lt;/role-name&gt;
      &lt;/auth-constraint&gt;
  &lt;/security-constraint&gt;
  
  &lt;login-config&gt;
      &lt;auth-method&gt;BASIC&lt;/auth-method&gt;
  &lt;/login-config&gt;
  
  &lt;security-role&gt;
      &lt;role-name&gt;admin&lt;/role-name&gt;
  &lt;/security-role&gt;
  &lt;security-role&gt;
      &lt;role-name&gt;user&lt;/role-name&gt;
  &lt;/security-role&gt;
  </code></pre>
  
  <p>When I start the Application and I call a URL which only admins and users can access I get the login popup from the browser. But if I logged in with correct user data the popup comes again. Other pages without a login working fine.</p>
  
  <p>There are no exceptions, no warnings, no other erros displayed in the console. </p>
  
  <p>How can I figured out whats the problem?</p>
  
  <p>SDK is Java 1.7<br>
  Tomcat version is 7.0</p>