The 8-hour Civil PE exam is a national exam, prepared by NCEES. According to NCEES, the Civil PE exam currently uses the 2003 IBC, and will do so throughout 2007.
The 2.5-hour seismic exam is a state exam, prepared by the California Board. Since the IBC is not yet effective in California, the seismic exam still uses the 2001 CBC. The 2001 CBC is based on the 1997 UBC, and you can use the 1997 UBC instead of the 2001 CBC if you like.
The 2.5-hour surveying exam is also a state exam, but it does not reference building codes.