Note: This blog post is from 2011. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.This isn't new info, but you may have missed it. If you're running CF 8 or 9, did you know you can and should update the JVM that came with it? And that you have Adobe's blessing to do this update? This is because of a serious bug in the JVM that is not fixed until 1.6.0_24.
Both CF 9.0 and 9.01 run on older JVMs (and therefore need this update). And are you on CF8? You're not left out: Adobe even has confirmed this update can be applied to CF 8 and 8.01, too!
Note: if you are finding this blog post because you're searching the web for help on updating the JVM that underlies ColdFusion, note that this is a very old post (2011) about one specific JVM version. Instead, for a more general discussion of updating the JVM, and especially about solving and preventing common problems when doing that, see my more "recent" (2014) and more elaborated post: CF911: 'Help! I've updated the JVM which ColdFusion uses, and now it won't start!'.
Still more updates since this originally was posted:
Update 1: Since I wrote this blog entry in Oct 2011, Adobe has since come out with a new technote in Oct 2012 saying that you are now permitted to update to any version of Java 1.6 (for CF 8/9/10).
Update 2: Since posting this note, I've realized I should document an important fact to be aware of if you DO update the JVM: after doing so, it may seem that changes you made to allow CFHTTP calls to SSL pages (or other tags in CFML that talk via SSL or TLS) may "seem to have been lost". The issue is likely that you had modified your current CF setup to import specific certificates for such sites, but those changes are "lost" when you change the JVM that CF is now using (which has its own keystore). But these cert changes can be recovered. For more on that, see the next to last section below.
Update 3: In Feb 2013, Adobe did come out with an update that authorizes moving to Java 1.7 in either 9 or 10. You must apply the update first, though. More in this Adobe blog entry.
Old news, but not everyone knows