Installation profile using hook_install_tasks(), tasks of the type batch do not work.

Same Issue : I have an implementation of hook_install_tasks in my .profile file. For tasks set to type 'batch', install_run_task within install.core.inc gets called for case batch, the $batch object is retrieved properly from the callback via
$batch = $function($install_state);

Seems like there's a problem with the call to batch_process within install.core.inc

Has anyone else faced this issue? If so, please help. Thanks.

Yes, was also following http://drupal.org/node/655190 and the documentation. Seems like support for that particular hook in .install files was added recently and one's supposed to use this in a .profile file generally. Does that make sense?

Tried implementing the same in my .install file as well, same issue.

function mymodule_install_tasks($install_state) {
        $flag = isset($install_state['flag']);
	$tasks = array();
	$tasks['install_mod'] = array(
		'display_name' => st('Install Mods'),
		'display' => TRUE,
		'type' => 'batch',
		'run' => $flag ? INSTALL_TASK_RUN_IF_NOT_COMPLETED : INSTALL_TASK_SKIP, 
		'function' => '_install_mods',
	);
	return $tasks;
}

function _install_mods() {
	global $install_state;
	$batch = array(
	  'title' => t('Installing Mods'),
	);
	//copying implementation from install.core.inc since module_enable does not seem to play well with Batch API
	$files = system_rebuild_module_data();
	foreach ($install_state['mods'] as $key => $module) {
    $batch['operations'][] = array('_install_module_batch', array($module, $files[$module]->info['name']));
  }
	return $batch;
}

The Batch does not get processed irrespective of whether this resides in my .install or .profile file.

I have a module that runs a batch process as part of it's install hook. When this module is installed either as from an install profiles's .info file, or as part of an instal task, the batch is not properly executed.

It is. In my .profile file, I have the following:

// Include only when in install mode. MAINTENANCE_MODE is defined in
// install.php and in drush_core_site_install().
if (defined('MAINTENANCE_MODE') && MAINTENANCE_MODE == 'install') {
  include_once('example.install.inc');
}

The hook_install_tasks are in example.install.inc

I think, though I'm not sure, that my problem is slightly different. It's not an insall task of type batch, but a module's hook_install implementation that is being installed in an install task using module_enable.