LDAPMod field types

[Bernd Jendrissek <bernd.jendrissek@rocketseed.com>]

I'm building a big piece of inherited code that uses OpenLDAP 
extensively, and now that we're (trying to) switch to FreeBSD 7.0, GCC 
complains quite a bit more than before:

43    modFormat.mod_op = LDAP_MOD_ADD;
44    modFormat.mod_type = "rocketseedFormat";
45    vformat[0] = "2";
46    vformat[1] = NULL;
47    modFormat.mod_values = vformat;

rscode/rocketutil/mydap.cpp:44: warning: deprecated conversion from 
string constant to 'char*'
rscode/rocketutil/mydap.cpp:45: warning: deprecated conversion from 
string constant to 'char*'

Are we risking some sort of free()-based crashes by populating the 
struct with string constants?  I grepped for mod_type in the OpenLDAP 
source and couldn't find any explicit dependency on the strings being 
dynamically allocated (except for ldap_mods_free(), which we don't 
call).  That doesn't mean there exists no such dependency!

Would it be safe to const_cast<char *> the string constants, or will I 
need to wrap each with a strdup() and ldap_mods_free() it all after 
we're done?

Thanks