It seems that in eras prior to July 10, 2001, spells that modify the same player attributes should stack if one contains an illusion component and the other does not. The examples given are for run speed (SoW and Wolf Form) and mana regen (Clarity and Lich).
http://everquest.allakhazam.com/hist...es-2001-2.html
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July 10, 2001 3:00 am
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- Stacking issues with 'change form' type spells have been corrected.
Lich and Clarity will no longer stack, nor will Spirit of Wolf and Wolf
Form.