Index: components/web-content/src/java/org/apache/jetspeed/portlet/SSOIFramePortlet.java
===================================================================
--- components/web-content/src/java/org/apache/jetspeed/portlet/SSOIFramePortlet.java	(revision 598778)
+++ components/web-content/src/java/org/apache/jetspeed/portlet/SSOIFramePortlet.java	(working copy)
@@ -165,13 +165,23 @@
         try
         {
             Subject subject = getSubject();
+            
             if (sso.hasSSOCredentials(subject, site))
             {
-                sso.updateCredentialsForSite(getSubject(), ssoPrincipal, site, ssoCredential);
+            	SSOContext context = sso.getCredentials(subject, site);
+            	if (!context.getRemotePrincipalName().equals(ssoPrincipal))
+            	{
+            		sso.removeCredentialsForSite(subject, site);
+            		sso.addCredentialsForSite(subject, ssoPrincipal, site, ssoCredential);
+            	} 
+            	else 
+            	{
+            		sso.updateCredentialsForSite(subject, ssoPrincipal, site, ssoCredential);
+            	}            	
             }
             else
             {
-                sso.addCredentialsForSite(getSubject(), ssoPrincipal, site, ssoCredential);
+                sso.addCredentialsForSite(subject, ssoPrincipal, site, ssoCredential);
             }
         }
         catch (SSOException e)