so i was stringing my magic shortbows (u) i had turned on double xp and i got 2400xp each bow, when double xp time was over i still had some short bows (u) in my bank so i thought it would be useless to turn on double xp for few bows. so i started to string them and i saw.... thing.... i got 2400xp each bow... again...

if some of u dont want to read, read this: double xp on 2400xp
                                                             double xp off 2400xp
                                                             i think it's a bug.