fix deprecations

conlib/session.inc

@@ -318,7 +318,7 @@ class cSession {
                 break;
             case "object":
                 ## $$var is an object. Enumerate the slots and serialize them.
-                eval("\$k = \$${var}->classname; \$l = reset(\$${var}->persistent_slots);");
+                eval("\$k = \${$var}->classname; \$l = reset(\$${var}->persistent_slots);");
                 $str.="\$$var = new $k; ";
                 while ($l) {
                     ## Structural recursion.