diff --git a/ChangeLog b/ChangeLog
index d96268b0a..3d27007eb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2004-04-25 Richard Frith-Macdonald <rfm@gnu.org>
+
+	* Source/NSProtocolChecker.m: Rewrite ... appeared almost totally
+	non-functional.
+
 2004-04-23  David Ayers  <d.ayers@inode.at>
 
 	* Source/Additions/GSLock.m ([GSLazyLock -init])
diff --git a/Headers/Foundation/NSProtocolChecker.h b/Headers/Foundation/NSProtocolChecker.h
index cecf13e31..cc1a9e9ea 100644
--- a/Headers/Foundation/NSProtocolChecker.h
+++ b/Headers/Foundation/NSProtocolChecker.h
@@ -36,18 +36,19 @@
 
 // Creating a checker
 
-+ (id) protocolCheckerWithTarget: (NSObject *)anObject
-			protocol: (Protocol *)aProtocol;
-- (id) initWithTarget: (NSObject *)anObject protocol: (Protocol *)aProtocol;
++ (id) protocolCheckerWithTarget: (NSObject*)anObject
+			protocol: (Protocol*)aProtocol;
+
+- (id) initWithTarget: (NSObject*)anObject
+	     protocol: (Protocol*)aProtocol;
 
 // Reimplemented NSObject methods
  
-- (void)forwardInvocation: (NSInvocation *)anInvocation;
-- (struct objc_method_description *) methodDescriptionForSelector: (SEL)aSelector;
+- (void) forwardInvocation: (NSInvocation*)anInvocation;
    
 // Getting information
-- (Protocol *) protocol;
-- (NSObject *) target;
+- (Protocol*) protocol;
+- (NSObject*) target;
 
 @end
 
diff --git a/Source/NSFileManager.m b/Source/NSFileManager.m
index 7f373d858..0cd0517fb 100644
--- a/Source/NSFileManager.m
+++ b/Source/NSFileManager.m
@@ -564,7 +564,7 @@ static NSFileManager* defaultManager = nil;
 #endif
 
   /* This is consitent with MacOSX - just return NO for an invalid path. */
-  if (path == nil)
+  if ([path length] == 0)
     return NO;
     
 #if defined(__MINGW__)
@@ -719,7 +719,7 @@ static NSFileManager* defaultManager = nil;
 #endif
 
   /* This is consitent with MacOSX - just return NO for an invalid path. */
-  if (path == nil)
+  if ([path length] == 0)
     return NO;
 
 #if	defined(__MINGW__)
diff --git a/Source/NSProtocolChecker.m b/Source/NSProtocolChecker.m
index 45563c7ff..7f6177353 100644
--- a/Source/NSProtocolChecker.m
+++ b/Source/NSProtocolChecker.m
@@ -3,26 +3,28 @@
 
    Written by:  Mike Kienenberger
    Date: Jun 1998
-   
+   Rewrite: Richard Frith-Macdonald
+   Date: April 2004
+
    This file is part of the GNUstep Base Library.
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
-   
+
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
-   
+
    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA.
 
    <title>NSProtocolChecker class reference</title>
    $Date$ $Revision$
-   */ 
+   */
 
 #include "config.h"
 #include "GNUstepBase/preface.h"
@@ -33,14 +35,13 @@
 
 @implementation NSProtocolChecker
 
-/*
+/**
  * Allocates and initializes an NSProtocolChecker instance that will
  * forward any messages in the aProtocol protocol to anObject, its
  * target. Thus, the checker can be vended in lieu of anObject to
  * restrict the messages that can be sent to anObject. Returns the
  * new instance.
  */
-
 + (id) protocolCheckerWithTarget: (NSObject*)anObject
 			protocol: (Protocol*)aProtocol
 {
@@ -48,51 +49,42 @@
 						      protocol: aProtocol]);
 }
 
+- (void) dealloc
+{
+  DESTROY(_myTarget);
+  [super dealloc];
+}
+
 /*
  * Forwards any message to the delegate if the method is declared in
  * the checker's protocol; otherwise raises an NSInvalidArgumentException.
  */
 - (void) forwardInvocation: (NSInvocation*)anInvocation
 {
-  unsigned int	length;
-  void		*buffer;
-  
-  if ((struct objc_method_description *)NULL
-    != [self methodDescriptionForSelector: [anInvocation selector]])
-    [[NSException exceptionWithName: NSInvalidArgumentException
-		  reason: @"Method not declared in current protocol"
-		  userInfo: nil] raise];
-      
-  [anInvocation invokeWithTarget: _myTarget];
-  
-  length = [[anInvocation methodSignature] methodReturnLength];
-  buffer = (void *)malloc(length);
-  [anInvocation getReturnValue: buffer];
-  
-  if (0 == strcmp([[anInvocation methodSignature] methodReturnType],
-		  [[anInvocation methodSignatureForSelector: 
-				  @selector(init: )] methodReturnType]) )
+  if (GSObjCIsInstance(_myTarget)
+    && ![_myProtocol descriptionForInstanceMethod: [anInvocation selector]])
     {
-      if (((id)buffer) == _myTarget)
-   	{
-	  buffer = self;
-	  [anInvocation setReturnValue: buffer];
-   	}
+      [NSException raise: NSInvalidArgumentException
+		  format: @"<%s -%@> not declared",
+        [_myProtocol name], NSStringFromSelector([anInvocation selector])];
+    }
+  else if (![_myProtocol descriptionForClassMethod: [anInvocation selector]])
+    {
+      [NSException raise: NSInvalidArgumentException
+		  format: @"<%s +%@> not declared",
+        [_myProtocol name], NSStringFromSelector([anInvocation selector])];
     }
-  
-  return;
-}
 
+  [anInvocation invokeWithTarget: _myTarget];
+}
 
 - (id) init
 {
-  _myProtocol = nil;
-  _myTarget = nil;
-  
+  self = [self initWithTarget: nil protocol: nil];
   return self;
 }
 
-/*
+/**
  * Initializes a newly allocated NSProtocolChecker instance that will
  * forward any messages in the aProtocol protocol to anObject, its
  * delegate. Thus, the checker can be vended in lieu of anObject to
@@ -102,41 +94,25 @@
  */
 - (id) initWithTarget: (NSObject*)anObject protocol: (Protocol*)aProtocol
 {
-  [super init];
-  
-  _myProtocol = aProtocol;
-  
-  ASSIGN(_myTarget, anObject);
-  
+  self = [super init];
+  if (self != nil)
+    {
+      _myProtocol = aProtocol;
+      ASSIGN(_myTarget, anObject);
+    }
   return self;
 }
 
-/*
- * Returns an Objective C description for a method in the checker's
- * protocol, or NULL if aSelector isn't declared as an instance method
- * in the protocol.
- */
-- (struct objc_method_description*) methodDescriptionForSelector: (SEL)aSelector
-{
-  return [_myProtocol descriptionForInstanceMethod: aSelector];
-}
-
-/*
+/**
  * Returns the protocol object the checker uses to verify whether a
- * given message should be forwarded to its delegate, or the protocol
- * checker should raise an NSInvalidArgumentException.
+ * given message should be forwarded to its delegate.
  */
 - (Protocol*) protocol
 {
-  if (nil == _myProtocol)
-    [[NSException exceptionWithName: NSInvalidArgumentException
-		  reason: @"No protocol specified"
-		  userInfo: nil] raise];
-  
   return _myProtocol;
 }
 
-/*
+/**
  * Returns the target of the NSProtocolChecker.
  */
 - (NSObject*) target