Notice: Undefined index: cache in dynamic_cache_should_run()

Enabling Dynamic Cache after a Drupal first installation $GLOBALS['conf']['cache'] is null

In my opinion the code:

function dynamic_cache_should_run() {
  // If the CURRENT cache setting is TRUE there is no reason to hijack or to
  // do any of the other checks that follow.
  if ($GLOBALS['conf']['cache']) {
    return FALSE;
  }

should be:

function dynamic_cache_should_run() {
  // If the CURRENT cache setting is TRUE there is no reason to hijack or to
  // do any of the other checks that follow.
  if (isset($GLOBALS['conf']['cache']) && $GLOBALS['conf']['cache'] == TRUE) {
    return FALSE;
  }

Let me know if this is correct and I'll make a patch.