I was investigating the issue number 2476115 from Aperture:
It boiled down to the Iso8601.toString method. It yields wrong results for floating times before 1985 when the current timezone is set to Asia/Kathmandu. on 01.01.1986 Kathmandu nudged the timezone offset from +0530 to +0545. And for some bizarre reason all floating dates before that time when converted from a string to DateTime and back to string return moved forward by 15 minutes.
To reproduce: set the timezone on your machine to Asia/Kathmandu and try to build the 1.0.rc2 release.
I tried to tweak the toString method, attached in the patch. I must admit that I don't fully comprehend why all those ifs are as they are, but my modification doesn't break any tests, makes the ical4j release build correctly in Kathmandu and fixes my problem 2476115.
Please examine it and apply that patch if it doesn't break anything else. If you'd like to do something different, please make sure that the build works correctly in Kathmandu.
(The patch also comments out a line in TimeZoneTest that failed outside australia, see my bug report for details).