On Fri, 29 Apr 2011 Martin Hensel submitted an update to the
mhchem
package.
Summary description: for typesetting chemical formulae, chemical equations and Risk and Safety (R and S) Phrases License type: lppl
Announcement text: ---------------------------------------------------------------------- fixed: incompatibility with biblatex ----------------------------------------------------------------------
This package is located at http://mirror.ctan.org/macros/latex/contrib/mhchem/ . More information is at http://www.ctan.org/pkg/mhchem (if the package is new it may take a day for that information to appear). We are supported by the TeX Users Group http://www.tug.org . Please join a users group; see http://www.tug.org/usergroups.html .
Thanks for the upload.
For the CTAN Team Rainer Schöpf