all to undefined function url()

I did not get this error until I updated to the latest Drupal 6.16 version, then I got this error. Turning off caching fixes the error but I'd rather not have to turn off caching.

Did that several times, still get the error.

Yes, same exact error. Only for the IPAuthenticated user, regular login works fine.

We are receiving the same message: Fatal error: Call to undefined function url() in /var/www/html/sites/all/modules/ipAuthenticator/ipauth.module on line 42

I have tried clearing the cache and still get the error. Unlike b0b, if I turn off caching, I get many more errors (though this particular one goes away).

We also recently updated to Drupal 6.16.

I'm changing status to active (though I'm a newbie, so let me know if that is wrong).

Any help is greatly appreciated.

To get around this problem, I added the following lines before the call to url()
include_once './includes/common.inc';
include_once './includes/path.inc';

I don't get how url() would ever work in ipauth_boot() as at this point the boot loader hasn't included common.inc where url() is defined.

Also, on the home page $_GET["q"] isn't defined, so around line 72 I added this line:
if (!isset($_GET['q'])) $_GET['q']='';
before
if ($_GET['q'] == 'user')

otherwise that line bombs.

Not sure if I solved the root of this problem, but these fixes worked for me.

I just wanted to say thanks. mhennings fix worked for me.
Thanks jhus for the response too.

I am having the same problem. When I disable caching it works though. I do not know where I apply the lines that mhenning proposed.

Am I supposed to apply these two lines:
include_once './includes/common.inc';
include_once './includes/path.inc';

at line 42 before the line:
url($_GET["q"], 'ipauth_no_cache='.md5(time()), NULL, TRUE);

Can someone help me out please?

Thank you!
This mod is great btw!!!

tways,
I'm copying the code around where mhenning inserted changes (which are noted in the comments as changes by saforian). I'm not a programmer, so hopefully I grabbed everything right (looks like some of the tabs gets messed up when I preview the code).
Hope this helps!

      if (variable_get('cache', CACHE_DISABLED) != CACHE_DISABLED && !isset($_GET['ipauth_no_cache'])) {
        // Reload the page, the query string ensures that there will be a page
        // cache miss and thus a fresh generated page is served.

		//SAFORIAN add this so url() works 
		include_once './includes/common.inc'; 
		include_once './includes/path.inc';   
		$url = url($_GET["q"], array('query'=>'ipauth_no_cache='.md5(time())));
		//old version that honestly I don't know how it ever worked without includes and format is wrong for D6
		//$url = url($_GET["q"], 'ipauth_no_cache='.md5(time()), NULL, TRUE);

        // Remove newlines from the URL to avoid header injection attacks.
        $url = str_replace(array("\n", "\r"), '', $url);

        // Before the redirect, allow modules to react to the end of the page request.
        module_invoke_all('exit', $url);

        // Even though session_write_close() is registered as a shutdown function, we
        // need all session data written to the database before redirecting.
        session_write_close();

        header('Location: '. $url, TRUE, 302);
        exit();
      }
    }
  }

	//SAFORIAN add the 0 here so this code won't be run and you can login
  if (0 || in_array($user->uid, ipauth_get_uids('enabled'))) {
    // It's one of the special ip_auth users, take the authenticated user role away.
    unset($user->roles[DRUPAL_AUTHENTICATED_RID]);
    $user->roles[DRUPAL_ANONYMOUS_RID] = 'anonymous user';

	//SAFORIAN, add this so calls down below don't bomb on home page where q isn't set
	if (!isset($_GET['q'])) $_GET['q']='';

    if (!_ipauth_path_allowed()) {
      drupal_access_denied();
      // Allow modules to react to the end of the page request.
      module_invoke_all('exit');
      exit();
    }