Buy a copy of Visual Slick Edit for Linux.
Great piece of software. But yes, quite expensive cake. http://www.slickedit.com/
Essentially, the rules for a TOS change require that a user is given notices of changes and an opportunity to accept or reject them. Websites that have unilateral wording in their Terms of Service have now had those documents struck down in court. This can have far reach consequences among the many many sites that have improperly worded Terms of Service.
The fix is easy though: Just change the wording to say that you will notify your users if the terms change and give them the ability to accept or reject the changes.
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