I spent the night desperately trying to deploy one of our applications on Oracle XE 10.2. The Oracle install was quick and painless (even though I had to basically remove the 9.2 Universal Client previously installed), but our product couldn't even create a simple trigger. I ran all the SQL script I could find in the install directories, modifying all the lines that seemed to trouble Oracle here and there, to no avail... and 3 hours later, I realised that this was Oracle 10.bloody.2.0, while the last version supported by our app is 10.1.0.2. Talk about wasting my life.
Since XE is not available for previous releases, and the Standard Edition is a 600Mb download, and it's 4 AM, i think this operation will be better "performed" tomorrow at the office. I want to cry. Once again, repeat with me: never EVER start any serious activity after 10.30 PM, unless you are paid to do so.