I'm testing out Subsonic and I really want to use Tomcat 7, so I fixed some of the problems the current version (4.6) has with TC7.
This information is mainly for the Subsonic developer(s), but might be useful for anyone else trying to use Tomcat 7.
1. CSRF error popups
This happens because TC7 sets httpOnly cookie flag to true by default and DWR 3.0.RC1 requires cookies to not have httpOnly.
More information
Relevant DWR bug (fixed in 3.0.RC2)
Solution: Upgrade to DWR 3.0.RC2
2. ELException in userSettings.jsp
Tomcat 7 is stricter regarding property names in EL expressions. All property names must be valid Java identifiers, but userSettings.jsp contains command.new references which aren't valid because "new" is a Java keyword.
Solution: Replace command.new with command['new'] in userSettings.jsp
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I haven't seen any other showstoppers yet, but I'll report further findings here!
I'll make a proper bug report in sourceforge once I've found enough problems and fixes.