diff --git a/ChangeLog b/ChangeLog
index 97c3b0daa..446bb6639 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2003-09-30  Derek Zhou <dzhou@chrontel.com>
+
+	* Source/NSCharacterSet.m: patch to ensure lock is created as
+	soon as the process goes multi-threaded, therefore avoiding
+	a race condition causing a rare exception.
+
 2003-09-26  Richard Frith-Macdonald <rfm@gnu.org>
 
 	* Source/NSString.m: Fix pathExtension bug reported by Roland
diff --git a/Source/Additions/GSMime.m b/Source/Additions/GSMime.m
index 89db2c5ec..66ba59e76 100644
--- a/Source/Additions/GSMime.m
+++ b/Source/Additions/GSMime.m
@@ -3377,6 +3377,7 @@ static NSCharacterSet	*tokenSet = nil;
 /**
  * Search the content of this document to locate a part whose content ID
  * matches the specified key.  Recursively descend into other documents.<br />
+ * Wraps the supplied key in angle brackets if they are not present.<br />
  * Return nil if no match is found, the matching GSMimeDocument otherwise.
  */ 
 - (id) contentByID: (NSString*)key
diff --git a/Source/NSCharacterSet.m b/Source/NSCharacterSet.m
index 223e010ec..418b57f8b 100644
--- a/Source/NSCharacterSet.m
+++ b/Source/NSCharacterSet.m
@@ -33,6 +33,8 @@
 #include "Foundation/NSLock.h"
 #include "Foundation/NSPathUtilities.h"
 #include "Foundation/NSDictionary.h"
+#include "Foundation/NSThread.h"
+#include "Foundation/NSNotification.h"
 
 static NSString* NSCharacterSet_PATH = @"NSCharacterSets";
 
@@ -43,6 +45,18 @@ static NSLock* cache_lock = nil;
 
 @implementation NSCharacterSet
 
++ (void) _becomeThreaded: (NSNotification*)notification
+{
+  if (cache_lock == nil)
+    {
+      cache_lock = [NSLock new];
+      [[NSNotificationCenter defaultCenter]
+	removeObserver: self
+		  name: NSWillBecomeMultiThreadedNotification
+		object: nil];
+    }
+}
+
 + (void) initialize
 {
   static BOOL one_time = NO;
@@ -57,6 +71,18 @@ static NSLock* cache_lock = nil;
 	}
       one_time = YES;
     }
+  if ([NSThread isMultiThreaded])
+    {
+      [self _becomeThreaded: nil];
+    }
+  else
+    {
+      [[NSNotificationCenter defaultCenter]
+        addObserver: self
+        selector: @selector(_becomeThreaded:)
+        name: NSWillBecomeMultiThreadedNotification
+        object: nil];
+    }
 }
 
 /* Provide a default object for allocation */
@@ -73,8 +99,6 @@ static NSLock* cache_lock = nil;
   NSString *set_path;
   NSBundle *bundle;
 
-  if (!cache_lock)
-    cache_lock = [NSLock new];
   [cache_lock lock];
 
   set = nil; /* Quiet warnings */