Leak problem with NSKeyedUnarchiver

Question

here I have some code where the Leaks-Instrument detects leaks. The commented Numbers behind some lines taken out from the Leaks-Instrument.

I don't know what I have to do here. I have made many tries, have released and autoreleased, but no solution.

Can somebody show me where the problem is?

- (void) handleDataModel {
 int theTag = [[themeDict valueForKey:KEY_TAG] intValue];
 NSString *theFilePath = [self dataFilePathFromParentTag:theTag]; //1.02kb
 NSString *strPath = [[[NSString alloc] initWithString:theFilePath] autorelease]; //32bytes
 NSMutableData *userData = [[NSMutableData alloc] initWithContentsOfFile:strPath]; //32bytes
 if (userData) {
  _dataModel = [self newUnarchiveData: userData]; //544bytes
 } else {
  _dataModel = [[[ThemeDataModel alloc] initWithDictionary:themeDict] autorelease];
 }
 _dataModel.Modules = [self sortArray:_dataModel.Modules]; //64bytes

 [self writeDataToFile:_dataModel]; //2,59kb

 [userData release];
 [strPath release];
}

- (NSString *)dataFilePathFromParentTag:(int)themeTag {
 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); //1.41kb
 NSString *documentsDirectory = [[paths objectAtIndex:0] retain];
 NSString *fileName = [NSString stringWithFormat:@"%iTheme", themeTag]; //96bytes
 NSString *theFile = [documentsDirectory stringByAppendingPathComponent:fileName]; //544bytes
 [documentsDirectory release];
 return theFile;
}

- (id) newUnarchiveData: (NSMutableData *) userData {
 NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:userData]; //352bytes
 id model = [unarchiver decodeObjectForKey:KEY_DATA]; //192bytes
 [unarchiver finishDecoding];
 [unarchiver release];
 return model;
}

- (void)writeDataToFile:(id)model {
 NSMutableData *data = [[NSMutableData alloc] init]; //32bytes
 [self archiveData:data model:model]; //1,30bytes
 [data writeToFile:[self dataFilePathFromParentTag:[[model valueForKey:KEY_TAG] intValue]] atomically:YES]; //1,27bytes
 [data release];
}

thank you xnz