With the latest patch provided by Mohan KR which added JSP support for layout-help, solo and maximized decorators.
I think this now completes this feature and I'm happy with it to incorporate it in the 2.1.1 release.
But please note: the JSP decorators are very new, and only available yet for the tigris theme, and should still be considered somewhat experimental.
What Mohan has provided so far works already very well though (great job Mohan!).
The JSP decorators can be enabled by modifying (properly commented) settings in:
Note: you need to change the settings in all of the above properties files, and then restart jetspeed.
Also note: for the tcolumns template there isn't a JSP replacement (yet), but that isn't much used anyway AFAIK.
Just to be sure: don't switch your page layout portlet(s) from columns to tcolumns, otherwise your page will be broken.