I\'m trying to test Coldfusion for learning purposes, but I really don\'t know what is the aditional features that the non-free Enterprise Edition add to the free Developer
The developer edition of Adobe ColdFusion Server is limited by IP addresses - only the localhost and 1 other IP address can access the server. Any more, and it will throw license exceptions.
Also, printable items such as documents created with cfdocument and cfpresentation are watermarked with a gigantic diagonal banner over each page.
Otherwise, the dev and enterprise editions both have all the features enabled, including advanced debugging and server monitoring, PDF & FlashPaper generation, advanced gateways, 64 bit CPU support and full database drivers including Oracle - the works.
The Trial edition of ColdFusion is the same as enterprise for 30 days, but then drops to be the developer edition after 30 days - once the license has expired. Do make sure you remember to get your serial number in if you put this on production :)
For reference, see Adobe ColdFusion Editions.