I consider this to be an apparent flaw in the server setup, which Serendipity is not responsible to fix. Sessions should work for each of the seperate hosts, and correct paths should be set in the Server configuration.
Adding the code to Serendipity skews the problem and introduces redundant code for 99% of all setups.
If you really need this, I suggest to put it inside .htaccess or serendipity_config_local.inc.php (which will be preserved by Serendipity on upgrades)
Regards,
Garvin
# Garvin Hicking (s9y Developer)
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