I recently bought a debian etch plesk vps. I noticed that there are both php4 & 5 installed on the system but only php4 is loaded with apache. I tried to enable the php5 module but i got error that libphp5.so couldn't be found. I asked my provider to check it out and replied that php4 to 5 is major upgrade and i should get charged for that. If i try to upgrade php4 to 5 my self what are the points i should be careful that might cause plesk stop working. thanks in advance.