my upgrades included doing this:
PHP upgraded from 4.x to 5.2.5 then backed it off to 5.2.4
Apache from 1.3 to 2.2
Mod_suphp is installed

there were some conflicts with upgrades and not really directly related to dolphin only. i run these other scripts and they were complaining just as much;
wordpress
b2Evo
e107
joomla
oscommerce
zencart

so upgrading a server can be a little tricky. you can install both php4 and php5 and the server will take care of any php4 calls. anyhow just thought see more i would add this.