Im using the following hunger/thirst/sleep mod -

http://www.nexusmods.com/morrowind/mods/43365/?

There seems to be a common bug in sleep penalties not resolving. Reading the comments it seems quite a few users have experienced it.

Would anyone be willing to make a fix? Or shed some light on whats causing the problem? The author himself hasn't run into the bug so seems happy to leave the mod as it is.