diff --git a/plugins/kolab_files/kolab_files.js b/plugins/kolab_files/kolab_files.js
index 0a1073ed..b168b734 100644
--- a/plugins/kolab_files/kolab_files.js
+++ b/plugins/kolab_files/kolab_files.js
@@ -230,6 +230,7 @@ function kolab_directory_selector_dialog(id)
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.' + label),
     buttons: buttons,
+    button_classes: ['mainaction'],
     minWidth: 250,
     minHeight: 300,
     height: 350,
@@ -283,6 +284,7 @@ function kolab_files_selector_dialog()
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.selectfiles'),
     buttons: buttons,
+    button_classes: ['mainaction'],
     minWidth: 500,
     minHeight: 300,
     width: 700,
@@ -340,7 +342,8 @@ function kolab_files_folder_create_dialog()
   // show dialog window
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.foldercreate'),
-    buttons: buttons
+    buttons: buttons,
+    button_classes: ['mainaction']
   });
 
   // Fix submitting form with Enter
@@ -395,7 +398,8 @@ function kolab_files_folder_edit_dialog()
   // show dialog window
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.folderedit'),
-    buttons: buttons
+    buttons: buttons,
+    button_classes: ['mainaction']
   });
 
   // Fix submitting form with Enter
@@ -467,6 +471,8 @@ function kolab_files_folder_mount_dialog()
    });
   }
 
+  args.button_classes = ['mainaction'];
+
   // show dialog window
   kolab_dialog_show(dialog, args, function() {
     $('td.source:first', dialog).click();
@@ -504,7 +510,8 @@ function kolab_files_file_edit_dialog(file)
   // show dialog window
   kolab_dialog_show(dialog, {
     title: rcmail.gettext('kolab_files.fileedit'),
-    buttons: buttons
+    buttons: buttons,
+    button_classes: ['mainaction']
   });
 };
 
diff --git a/plugins/kolab_notes/notes.js b/plugins/kolab_notes/notes.js
index d6e43d61..0f342e59 100644
--- a/plugins/kolab_notes/notes.js
+++ b/plugins/kolab_notes/notes.js
@@ -1271,6 +1271,7 @@ function rcube_kolab_notes_ui(settings)
 
             buttons.push({
                 text: rcmail.gettext('save'),
+                'class': 'mainaction',
                 click: function() {
                     save_note(beforesave);
                     dialog.dialog('close');
@@ -1295,7 +1296,7 @@ function rcube_kolab_notes_ui(settings)
                 open: function(event, ui) {
                     $(this).parent().find('.ui-dialog-titlebar-close').hide();
                     setTimeout(function(){
-                        dialog.parent().find('.ui-button:visible').first().addClass('mainaction').focus();
+                        dialog.parent().find('.ui-button:visible').first().focus();
                     }, 10);
                 },
                 close: function(event, ui) {
diff --git a/plugins/kolab_tags/kolab_tags.js b/plugins/kolab_tags/kolab_tags.js
index 0afd78e8..9e93af7e 100644
--- a/plugins/kolab_tags/kolab_tags.js
+++ b/plugins/kolab_tags/kolab_tags.js
@@ -159,6 +159,7 @@ function manage_tags()
         rcmail.gettext('kolab_tags.tags'),
         [{
             text: rcmail.gettext('save'),
+            'class': 'mainaction',
             click: function() { if (tag_form_save()) $(this).dialog('close'); }
         },
         {
diff --git a/plugins/tasklist/tasklist.js b/plugins/tasklist/tasklist.js
index f107a39c..9f02353e 100644
--- a/plugins/tasklist/tasklist.js
+++ b/plugins/tasklist/tasklist.js
@@ -1937,6 +1937,7 @@ function rcube_tasklist_ui(settings)
 
             buttons.push({
                 text: rcmail.gettext('delete','tasklist'),
+                'class':'delete',
                 click: function() {
                     if (delete_task(me.selected_task.id))
                         $dialog.dialog('close');
@@ -2240,6 +2241,9 @@ function rcube_tasklist_ui(settings)
           resizable: (!bw.ie6 && !bw.ie7),  // disable for performance reasons
           closeOnEscape: false,
           title: rcmail.gettext((action == 'edit' ? 'edittask' : 'newtask'), 'tasklist'),
+          open: function() {
+              $dialog.parent().find('.ui-button:not(.ui-dialog-titlebar-close)').first().addClass('mainaction');
+          },
           close: function() {
               rcmail.ksearch_blur();
               editform.hide().appendTo(document.body);