The OEM foglight kit description shown on Handa Accessories for the 2001-2005 Civic specifically says, "Not for Hybrid Model." The page also lists PDF files for how to install the foglight kit on all non-hybrid civics.

http://www.handaaccessories.com/civext01.html

If you choose to bypass the warning, let me know how it goes. I've been thinking about foglights myself.