Index: /CKEditor/branches/prototype/_source/plugins/dialogui/plugin.js
===================================================================
--- /CKEditor/branches/prototype/_source/plugins/dialogui/plugin.js	(revision 2718)
+++ /CKEditor/branches/prototype/_source/plugins/dialogui/plugin.js	(revision 2719)
@@ -457,4 +457,10 @@
 						attributes = { 'class' : 'cke_dialog_ui_input_select' };
 
+					// Add multiple and size attributes from element definition.
+					if ( elementDefinition.size != undefined )
+						attributes.size = elementDefinition.size;
+					if ( elementDefinition.multiple != undefined )
+						attributes.multiple = elementDefinition.multiple;
+
 					cleanInnerDefinition( myDefinition );
 					for ( var i = 0, item ; i < elementDefinition.items.length && ( item = elementDefinition.items[i] ) ; i++ )
@@ -482,5 +488,8 @@
 				if ( arguments.length < 3 )
 					return;
-				
+
+				if ( elementDefinition['default'] === undefined )
+					elementDefinition['default'] = '';
+
 				var _ = CKEDITOR.tools.extend( initPrivateObject.call( this, elementDefinition ), { definition : elementDefinition, buttons : [] } );
 
Index: /CKEditor/branches/prototype/_source/plugins/forms/dialogs/select.js
===================================================================
--- /CKEditor/branches/prototype/_source/plugins/forms/dialogs/select.js	(revision 2718)
+++ /CKEditor/branches/prototype/_source/plugins/forms/dialogs/select.js	(revision 2719)
@@ -271,4 +271,5 @@
 								label : '',
 								title : '',
+								multiple : true,
 								size : 5,
 								style : 'width:105px',
@@ -295,4 +296,5 @@
 								label : '',
 								title : '',
+								multiple : true,
 								size : 5,
 								style : 'width:105px',