Add implementation for validateUserInterfaceAction:

Source/NSTextCheckingController.m

@@ -23,6 +23,7 @@
 */
 
 #import "AppKit/NSTextCheckingController.h"
+#import "AppKit/NSSpellChecker.h"
 
 @implementation NSTextCheckingController
 
@@ -61,6 +62,13 @@
 
 - (void) checkSpelling: (id)sender
 {
+    int wordCount = 0;
+  [[NSSpellChecker sharedSpellChecker] checkSpellingOfString: [_client string]
+                                                  startingAt: 0
+                                                    language: nil
+                                                        wrap: NO
+                                      inSpellDocumentWithTag: _spellCheckerDocumentTag
+                                                   wordCount: &wordCount];
 }
 
 - (void) checkTextInRange: (NSRange)range 

Source/NSTextFinder.m

@@ -185,6 +185,13 @@
 
 - (BOOL) validateUserInterfaceAction: (id<NSValidatedUserInterfaceItem>)item
 {
+  SEL action = [item action];
+  if (sel_isEqual(action, @selector(performTextFinderAction:)) ||
+      sel_isEqual(action, @selector(performFindPanelAction:)))
+    {
+      return [self validateAction: [item tag]];
+    }
+
   return YES;
 }