cached comment_form block submits to wrong node

I'm surprised this issue hasn't been raised before because it seems so critical -- but maybe it's because I'm doing something wrong?

Symptom:

Comments submitted from the comment_form block on node pages get posted to wrong node. Replies to other comments are fine.

Problem:

The block is being cached per role, so the form's action url points to the wrong node.

Quick fix:

Update database to NOT cache the comment_form block. Clear cache.

mysql> update blocks set cache = -1 where module = 'commentblock' and delta = 'comment_form';

Real fix:

Blocks default to BLOCK_CACHE_PER_ROLE if not specified in hook_block op=list.

Attached is a patch to set the comment_form block's "cache" setting to BLOCK_NO_CACHE. (It'd be better if we could cache the block per-role and per-page, but that option doesn't seem to exist.)

http://api.drupal.org/api/function/hook_block/6

Also attached is a commentblock.install file with the update function to run the sql update.

HTH.
Greg