Some characters converted to HTML entities by token_replace

To reproduce:

• Create a post with an apostrophe in the title
• Subscribe to the post, make a comment
• Since [comment:node:title] is in the subject pattern, the title will be check_plain'ed and the subject will contain ' instead of the apostrophe

This issue is the same as reported previously under the Comment Notify module:

• some characters converted to HTML entities by token_replace