Add missing -[description] to XMPPStringPrepFailedException.

src/XMPPExceptions.m

@@ -70,9 +70,8 @@
 		return description;
 
 	pool = [[OFAutoreleasePool alloc] init];
-	description = [[OFString alloc]
+	description = [[OFString alloc] initWithFormat:
-	    initWithFormat: @"An exception occurred in class %@!",
+	    @"An exception occurred in class %@!", [self className]];
-			    [self className]];
 	[pool release];
 
 	return description;
@@ -128,4 +127,20 @@
 
 	[super dealloc];
 }
+
+- (OFString*)description
+{
+	OFAutoreleasePool *pool;
+
+	if (description != nil)
+		return description;
+
+	pool = [[OFAutoreleasePool alloc] init];
+	description = [[OFString alloc] initWithFormat:
+	    @"Stringprep with profile %@ failed on string '%@'!",
+	    profile, string];
+	[pool release];
+
+	return description;
+}
 @end