Hi,

I solved this recent problem I had, not sure if it's anywhere but may help people in the future.
Something to do with PHP 5.2 to 5.3 differences, I'm running php 5.3 and Drupal 6.20

Just change (global replace) '&$node' to '$node' in the following hotspot module files:

hotspot.module
hotspot.pages.inc

Cheers,
Jason