Patch by Robert Scheck <robert@fedoraproject.org> for zarafa >= 6.40.0, which removes a wrong include causing a build failure on native Fedora 11 and/or later as well as on RHEL 4 and/or later. According to some Kerberos people, "com_err.h" is already included by the "krb5.h" include and thus doesn't need to be included once more. The build failure on RHEL/Fedora is caused due the non-existence of this include, on RHEL/ Fedora, only "<et/com_err.h>" would be available. If you really need the "com_err.h" for some other Linux distributions (where I didn't find a real difference so far), you have to conditionalize the include using preprocessor flags after detection in ./configure. --- zarafa-6.40.0/provider/libserver/ECKrbAuth.cpp 2010-05-31 19:28:59.000000000 +0200 +++ zarafa-6.40.0/provider/libserver/ECKrbAuth.cpp.krb5 2010-06-05 21:48:51.000000000 +0200 @@ -58,7 +58,6 @@ // error_message() is wrongly typed in c++ context extern "C" { #include <krb5.h> -#include <com_err.h> } ECRESULT ECKrb5AuthenticateUser(const std::string &strUsername, const std::string &strPassword, std::string *lpstrError)