[keycloak-user] When using Keycloak as SP in SAML via filter i.e. SamlFilter, we get exception (details inside)

Hi Folks, We have configured Keycloak as an SP via filter. Keycloak Version 1.7.0 We get this exception: ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[localhost].[/].[AppName]] Servlet.service() for servlet NasDefault threw exception: java.lang.RuntimeException: This method is not supported in a restored authenticated request at org.keycloak.adapters.servlet.FilterSessionStore$1.getDateHeader(FilterSessionStore.java:178) [:1.7.0.CR1] at org.apache.catalina.servlets.DefaultServlet.checkIfModifiedSince(DefaultServlet.java:1731) [:] at org.apache.catalina.servlets.DefaultServlet.checkIfHeaders(DefaultServlet.java:608) [:] at org.apache.catalina.servlets.DefaultServlet.serveResource(DefaultServlet.java:714) [:] at org.apache.catalina.servlets.DefaultServlet.doGet(DefaultServlet.java:368) [:] at javax.servlet.http.HttpServlet.service(HttpServlet.java:734) [:1.0.0.Final] at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) [:1.0.0.Final] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:324) [:] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:242) [:] ... (trimmed) ... at org.keycloak.adapters.saml.servlet.SamlFilter.doFilter(SamlFilter.java:125) [:1.7.0.CR1] ...(trimmed) ... etc. Any ideas on what this error means? Thanks, Regards, Akshay