I'm not sure if I'm missing something on my Redmine installation, but when I go to Gantt view and when I'm using the Sprints module, all issues associated with a particular sprint, should appears below the sprint.
In my case, the appear tottally disassociated.
See attached screenshots
RE: Gantt structure - Added by Felix Schäfer almost 12 years ago
IIRC the issues and versions are listed in whatever order you have set in the filter at the top, the default probably being by ID or something. There's a gantt rewrite in trunk, though I'm not sure what has changed in it (I don't use gantt myself).
RE: Gantt structure - Added by Bernard Steens almost 12 years ago
I have the same on my enviroment after upgrade to trunk revison 4226, with my old version 3779 the subtasks in gantt were almost funtianal.
I added an issue ( #6693 ) for this problem.