Assume you have your project versioned in CVS and you either have its branch
somewhere, or checked out the same project to a different location.
1) Change something in copy/branch, save it and commit it.
2) In the trunk (another branch, or another location) change the same line in a
different way and save it.
3a) If you used branches, invoke CVS -> Merge Changes from Branch... on the
project root in Projects view and the previously changed branch into currently
used one.
3b) If you used same project checked out to a different location, invoke CVS ->
Update on the project root.
Result: Local conflict of versioned files occurs and in project view, instead of
the filename (eg. newfile.c) appears a file from local CVS cache (eg.
.#newfile.c.1.c). You have to remove it from the Projects view and add your
"old" file if you want to work with it (even after the conflict is resolved). In
the Files view, everything is OK, but not in the Projects view.

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  Product Version         = NetBeans IDE 5.5 (Build 200610171010)
  Operating System        = Windows XP version 5.1 running on x86
  Java                    = 1.5.0_09
  VM                      = Java HotSpot(TM) Client VM 1.5.0_09-b03
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