It seems like having HungerStrike enabled leaves the Lexica Botania from Botania in a state where it can't be opened, removing HS fixes the issue. Here's the code for it:
https://github.com/Vazkii/Botania/blob/master/MODSRC/vazkii/botania/common/item/ItemLexicon.java#L53

Mod List (with forge 1048):

Could you verify whether this is a problem with 1.7.2.0 or not?

I was able to reproduce the problem (on both 1.7.2.0 and 1.7.2.1). I'll look a bit more to see if I can see a cause for the conflict.

Release hs-1.7.2.2 should solve this problem. It was related to how the server/client side was checked when hunger strike was enabled. The problem would not surface until hunger strike was turned on for a player, but then the only way to correct it would be restarting the server.