new file mode 100644
--- /dev/null
+++ b/library/smarty/libs/sysplugins/smarty_internal_compile_assign.php
@@ -0,0 +1,84 @@
+<?php
+/**
+ * Smarty Internal Plugin Compile Assign
+ * Compiles the {assign} tag
+ *
+ * @package    Smarty
+ * @subpackage Compiler
+ * @author     Uwe Tews
+ */
+
+/**
+ * Smarty Internal Plugin Compile Assign Class
+ *
+ * @package    Smarty
+ * @subpackage Compiler
+ */
+class Smarty_Internal_Compile_Assign extends Smarty_Internal_CompileBase {
+    /**
+     * Compiles code for the {assign} tag
+     *
+     * @param  array $args array with attributes from parser
+     * @param  object $compiler compiler object
+     * @param  array $parameter array with compilation parameter
+     *
+     * @return string compiled code
+     */
+    public function compile($args, $compiler, $parameter) {
+        // the following must be assigned at runtime because it will be overwritten in Smarty_Internal_Compile_Append
+        $this->required_attributes = array('var', 'value');
+        $this->shorttag_order = array('var', 'value');
+        $this->optional_attributes = array('scope');
+        $_nocache = 'null';
+        $_scope = Smarty::SCOPE_LOCAL;
+        // check and get attributes
+        $_attr = $this->getAttributes($compiler, $args);
+        // nocache ?
+        if ($compiler->tag_nocache || $compiler->nocache) {
+            $_nocache = 'true';
+            // create nocache var to make it know for further compiling
+            if (isset($compiler->template->tpl_vars[trim($_attr['var'], "'")])) {
+                $compiler->template->tpl_vars[trim($_attr['var'], "'")]->nocache = true;
+            } else {
+                $compiler->template->tpl_vars[trim($_attr['var'], "'")] = new Smarty_Variable(null, true);
+            }
+        }
+        // scope setup
+        if (isset($_attr['scope'])) {
+            $_attr['scope'] = trim($_attr['scope'], "'\"");
+            if ($_attr['scope'] == 'parent') {
+                $_scope = Smarty::SCOPE_PARENT;
+            } elseif ($_attr['scope'] == 'root') {
+                $_scope = Smarty::SCOPE_ROOT;
+            } elseif ($_attr['scope'] == 'global') {
+                $_scope = Smarty::SCOPE_GLOBAL;
+            } else {
+                $compiler->trigger_template_error('illegal value for "scope" attribute', $compiler->lex->taglineno);
+            }
+        }
+        // compiled output
+        if (isset($parameter['smarty_internal_index'])) {
+            $output = "<?php \$_smarty_tpl->createLocalArrayVariable($_attr[var], $_nocache, $_scope);\n\$_smarty_tpl->tpl_vars[$_attr[var]]->value$parameter[smarty_internal_index] = $_attr[value];";
+        } else {
+            // implement Smarty2's behaviour of variables assigned by reference
+            if ($compiler->template->smarty instanceof SmartyBC) {
+                $output = "<?php if (isset(\$_smarty_tpl->tpl_vars[$_attr[var]])) {\$_smarty_tpl->tpl_vars[$_attr[var]] = clone \$_smarty_tpl->tpl_vars[$_attr[var]];";
+                $output .= "\n\$_smarty_tpl->tpl_vars[$_attr[var]]->value = $_attr[value]; \$_smarty_tpl->tpl_vars[$_attr[var]]->nocache = $_nocache; \$_smarty_tpl->tpl_vars[$_attr[var]]->scope = $_scope;";
+                $output .= "\n} else \$_smarty_tpl->tpl_vars[$_attr[var]] = new Smarty_Variable($_attr[value], $_nocache, $_scope);";
+            } else {
+                $output = "<?php \$_smarty_tpl->tpl_vars[$_attr[var]] = new Smarty_Variable($_attr[value], $_nocache, $_scope);";
+            }
+        }
+        if ($_scope == Smarty::SCOPE_PARENT) {
+            $output .= "\nif (\$_smarty_tpl->parent != null) \$_smarty_tpl->parent->tpl_vars[$_attr[var]] = clone \$_smarty_tpl->tpl_vars[$_attr[var]];";
+        } elseif ($_scope == Smarty::SCOPE_ROOT || $_scope == Smarty::SCOPE_GLOBAL) {
+            $output .= "\n\$_ptr = \$_smarty_tpl->parent; while (\$_ptr != null) {\$_ptr->tpl_vars[$_attr[var]] = clone \$_smarty_tpl->tpl_vars[$_attr[var]]; \$_ptr = \$_ptr->parent; }";
+        }
+        if ($_scope == Smarty::SCOPE_GLOBAL) {
+            $output .= "\nSmarty::\$global_tpl_vars[$_attr[var]] = clone \$_smarty_tpl->tpl_vars[$_attr[var]];";
+        }
+        $output .= '?>';
+
+        return $output;
+    }
+}