--- Server.php	2007-11-13 16:50:53.000000000 -0500
+++ Server_new.php	2008-01-31 17:02:05.000000000 -0500
@@ -132,9 +132,14 @@
                     $func_args = $this->_functions[$this->_method]->getParameters();
 
                     $calling_args = array();
+                    $required_args = array();
                     foreach ($func_args as $arg) {
-                        if (isset($request[strtolower($arg->getName())])) {
-                            $calling_args[] = $request[strtolower($arg->getName())];
+                        $lower_arg_name = strtolower($arg->getName());
+                        if (isset($request[$lower_arg_name])) {
+                            $calling_args[] = $request[$lower_arg_name];
+                        }
+                        if (!$arg->isOptional()) {
+                            $required_args[] = $lower_arg_name;
                         }
                     }
 
@@ -145,8 +150,8 @@
                         }
                     }
 
-                    if (count($calling_args) < count($func_args)) {
-                        throw new Zend_Rest_Server_Exception('Invalid Method Call to ' . $this->_method . '. Requires ' . count($func_args) . ', ' . count($calling_args) . ' given.', 400);
+                    if (count($calling_args) < count($required_args)) {
+                        throw new Zend_Rest_Server_Exception('Invalid Method Call to ' . $this->_method . '. Requires ' . count($required_args) . ', ' . count($calling_args) . ' given.', 400);
                     }
 
                     if ($this->_functions[$this->_method] instanceof Zend_Server_Reflection_Method) {