We need this functionality as well so I took the 2.6.1 beta release and made some pretty heavy changes. It seems to be working so I documented the changes I made and repackaged it as a dot release, hope I'm not stepping an any toes. Here is a summary of what I did:
- Moved the 'subscribeforums.php' code into a plugin, EI_SubscribeForums, using the usersub_start hook location.
- Also had to add a plugin, EI_EnableSubscription, using the usersub_add_complete hook point to enable the proper options in the drop-down when subscribing to the form.
- Templates, USERCP_SUB_MGR and usercp_sub_mgr_forumbits, modified to use the vB4 layout methods.
- Changed the USERCP_SHELL mod in the instructions to use a list instead of tables.
- Modified the template, subscribe_choosetype, changing the first if condition to look at "$type=='threadid'" to determine if this is a thread or a forum.
Note - this is still largely untested but it seems to be working as originally designed.