uiwebview and huge memory loss

I have a problem using UIWebViews, I've seen the same question here but there wasn't helpful answer. the question is here: UIWebView memory management . I will quote it:

I am developing an application that makes heavy use of UIWebView. This app generates dynamically lots of UIWebViews while loading content from my server. Some of these UIWebViews are quite large and have a lot of pictures.

If I use instruments to detect leaks, I do not detect any. However, lots of objects are allocated and I suspect that has to do with the UIWebViews.

When the webviews release because no longer needed, it appears that not all memory is released. I mean, after a request to my server the app creates an UITableView and many webviews (instruments say about 8Mb). When user tap back, all of them are released but memory usage only decrements about 2-3 Mb, and after 5-10 minutes using the app it crashes.

I have created simple test app and have the same results.

It's a tableView, I'm creating DetailsView like this:

DetailsVC *detailViewController = [[DetailsVC alloc] initWithNibName:@"DetailsVC" bundle:nil];
detailViewController.n = indexPath.row;
[self.navigationController pushViewController:detailViewController animated:YES];
[detailViewController release];

in DetailsVC I have a webView created in IB. I load html like this:

    NSString *urlAddress;
if (self.n == 0)
{
    urlAddress = @"http://www.google.com";
}
else 
{
    urlAddress = @"http://www.yahoo.com";
}

NSURL *url = [NSURL URLWithString:urlAddress];

NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];

[self.webView loadRequest:requestObj];

I also do:

- (void)viewDidUnload {
self.webView = nil;
}

That's it, every time I choose any webView in RootViewController I'm loosing 2-3 Mb of memory, Is there a solution to this problem?

Thanks.