Ok I have been doing this for a while now and noticed a few others have been asking about it.
What this will do is show you how to change a users notification options without having to log in as them etc. I use it to force every user on my site to get an email everytime new news is posted.
This isn't a great solution but just a work around really. I was thinking of making a module to control all the notifications but quite frankly couldn't be bothered as I only have a small site and its not a huge deal for me to do the process below. Here is the process i follow. If anyone has a simplier way please let me know or if anyone is thinking of developing a module or hack for this I'm happy to help I just don't have the time to do this all myself.
Every time a new user registers I get a notification. I then go into phpMyAdmin to edit the database directly. Your host may use alternative methods.
First you need to find 2 pieces of info. the id of the person just registered and the module number for your news module.
So first view the data in the xoops_users table and make a note of the last uid created or the uid of the desired user.
Then open xoops_modules and find the mid of the news module.
Then finally in the table xoops_xoopsnotifications add a new line using the supplied form in phpmyadmin or writing a sql statment if you know how with this data:
not_id = *leave blank as it automatically increments*
not_modid = *news module id (mine is 5)*
not_itemid = 0
not_category = global
not_event = new_story
not_uid = *the user id of the desired user*
not_mode = 0
**Note**
This is only the notification to email a user everytime any news item is posted. If you wish to use other events or modules add a notification for yourself then view this table. It will be the last notification added and change the values for not_event and not_category as shown.
Good luck, this method works 100% for me and i have never had a problem but as usual I take no responsibility if you stuff it up and destroy you DB some how. Make sure its all backed up.