Development of the SMFforum Integration module for Drupal is no longer. Amy Stephen over at OpenSourceCommunity.org pointed out on her blog that the module's project leader, "vb", pulled the module due to licensing disagreements with SMF LLC. Amy references vb's original post at the Drupal forum, but she has a lot more to say. Amy's an active participant in the Joomla! community, a community which had their own issues with a bridge between Joomla! and SMF.
According to vb's post, an email sent by Michael "Oldiesmann" Eshom, Project Manager, Simple Machines LLC stated that:
The problem isn't with the smfforum.module file or the packages distributed on drupal.org. The problem is with the "smf_api_subs.php" file that you're distributing as part of the smf api package - it contains modified versions of several SMF functions, and you did not ask for permission to use this code or distribute it.
It appears that Simple Machines LLC doesn't have so much of a problem with bridging SMF and Drupal as much as they have issues with their own code being used without proper permission. The Simple Machines License clearly states that "Any Distribution of a Modified Package or derivative requires express written consent from Simple Machines LLC." No word on whether Simple Machines LLC would endorse the use of their code if permission is asked.