It says in the spell description 3 turns +1/lvl, but it's only lasting about 1 minute in total for a 19th lvl character.
Has it been marked down to Rounds per level?
It seems a tad short, for it makes a wonderful RP spell as well as being able to add to one's allies in a fight.
Perhaps put it to the 3 turns, +1 round/level? this will leave plenty of time for RPing and Combat if it's called for.