Pretty simple, a toggle command so self spells can't be neutralized.

I would love this, so many times on gmoons or getting spelled by higher levels I have to damage my SS gear or go afk for like 3 minutes so my spells run because I cant outspell my old spells.

Good idea, agree.

Would like to revive this idea, this is a much needed command. Many times on gmoons or when someone spells me on my way to do AT, i just have to sit there for 3-4 minutes waiting for them to run out doing nothing not sure how long my buff lasts because I cant risk swapping to my spell set mid combat.

Looks easy enough to do.
I'd just make the change in the skill_driver.c file in the add_spell method.
Well prob create new method, add_spell_to_self and do the check if flag is on in there etc.
Of course u need to add the toggle feature as well.
Well thats my 2 cents anyway

Couple things could be done, either like you said make a new function called for adding spells to self or adjusting add_spell to always pass both cn and co, and having the check in add_spell. Think a new function would be less code changes, since it would only require adjusting bless,pro,ew,ms,light instead of adjusting every place add_spell() currently exists. Either way though, the functions that call add_spell are already passing around cn, and co. so it would be fairly simple to add. That and flag switching is simple enough, assuming we have bits open for a new flag.

CF is full.
I have already started CF2 - so plenty of room again.

This is on the list.