issue with max mana

When I used /max it's showing that I have 310 base mana and the max is 300. I think this came from using a mana scroll and it must have put me over the max somehow.

Yes this is a bug and has been a bug since the dawn of time.

However, it was not detectable previously as the max mod able to be shown in the client was 999 so when the mod exceeded this the display was truncated to 999.

The bug was only able to be noticed when /max showed the true base value for mana/hp/end.

The cause was the hp/end/mana scrolls not checking limits correctly (as you suspected).

This bug has not been fixed and will be active next time I restart the server.

Well reported and diagnosed.