This bug fix request was originally posted by @Wisp
for some winking*) in the Feature Request forum and got buried within the 400+ other requests, so I thought I'd report it here (the original post can be found here
Effect 243 (Drain item charges) used to work in SoA, but it was buggy and sometimes it would destroy items seemingly at random, even ones without charges (including quest items). Bioware "fixed" this in ToB by simply disabling the entire effect.
It would be ever so nice if this effect could be restored to working order (sans the bugs). Additionally, I think it would be neat if the effect could be expanded to take the number of charges to be drained as its parameter 2 (currently thought to be unused).EXPECTED BEHAVIOR:
Expected/desired behaviour is adapted from the spell description of the summon nishruu spell and presented in a IESDP-like format:
243 (0x0F3) Item: Drain Item Charges 
Parameter #1: Item Type
Parameter #2: Number to Drain
Magical items matching the 'Item Type' value on the targeted creature(s) will have their charges drained by Number to Drain. Non-recharging items drained of all their charges are destroyed.
Known values for 'Item Type' are:
0 Magical items excluding weapons
1 Magical items including weapons
I do not know what is exactly feasible, but conceivably this effect could limit itself to draining charges from ability headers of type 3 (magical ability), and only destroying the item if the word at 0x24 in the ability header is not 3 (i.e., don't destroy recharging items) and if said charge count reaches 0 as a result of the drain.
NB. If the number-to-drain bit is implemented, the existing uses of this effect need to be amended to have a non-zero value for parameter 2. For reference, these are nishruu.itm, spellh01.itm, golmag01.itm, spin550.spl and spwm140.spl.