I've been getting this error for about a week or so.
[2007/09/14 22:27:57-877-x1]: Cartographer_Fishing-1.0\addon.lua:318: AceModuleCore-2.0: Cannot find module "Professions".
AceAddon-2.0-46764 (Ace2):483: in function <Interface\AddOns\Ace2\AceAddon-2.0\AceAddon-2.0.lua:460>
<in C code>: ?
AceEvent-2.0-48673 (Ace2):299: in function `TriggerEvent'
AceEvent-2.0-48673 (Ace2):958: in function <Interface\AddOns\Ace2\AceEvent-2.0\AceEvent-2.0.lua:951>
Cartographer_Professions is enabled and loaded, and it is handling herbalism and mining normally. I only get this error on characters that have the Fishing module enabled.
Fishing rev: r48851
Professions rev: r48782
I don't know if this is significant, but I noticed that the revision indicated in Professions.lua didn't match the rest of Cartographer, so I deleted the Cart and Cart-Professions folders and reinstalled using WAU. It's still showing that revision in Professions.