diff --git a/tests/test-backout b/tests/test-backout
--- a/tests/test-backout
+++ b/tests/test-backout
@@ -123,4 +123,37 @@ hg update -C
 
 hg backout -d '6 0' --parent 3 4
 
+cd ..
+
+echo '# named branches'
+
+hg init named_branches
+cd named_branches
+
+echo default > default
+hg ci -d '0 0' -Am default
+hg branch branch1
+echo branch1 > file1
+hg ci -d '1 0' -Am file1
+hg branch branch2
+echo branch2 > file2
+hg ci -d '2 0' -Am file2
+hg backout -d '3 0' -r 1 -m 'backout on branch1'
+# XXX maybe backout shouldn't suggest a merge here as it is a different branch?
+
+echo '% on branch2 with branch1 not merged, so file1 should still exist:'
+hg id
+hg st -A
+
+echo '% on branch2 with branch1 merged, so file1 should be gone:'
+hg merge
+hg ci -d '4 0' -m 'merge backout of branch1'
+hg id
+hg st -A
+
+echo '% on branch1, so no file1 and file2:'
+hg co -C branch1
+hg id
+hg st -A
+
 exit 0
diff --git a/tests/test-backout.out b/tests/test-backout.out
--- a/tests/test-backout.out
+++ b/tests/test-backout.out
@@ -62,3 +62,28 @@ rolling back last transaction
 1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 removing c
 changeset 5:033590168430 backs out changeset 4:b2f3bb92043e
+# named branches
+adding default
+marked working directory as branch branch1
+adding file1
+marked working directory as branch branch2
+adding file2
+removing file1
+changeset 3:f1c642b1d8e5 backs out changeset 1:bf1602f437f3
+the backout changeset is a new head - do not forget to merge
+(use "backout --merge" if you want to auto-merge)
+% on branch2 with branch1 not merged, so file1 should still exist:
+45bbcd363bf0 (branch2)
+C default
+C file1
+C file2
+% on branch2 with branch1 merged, so file1 should be gone:
+0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+(branch merge, don't forget to commit)
+21d4dc6f9a41 (branch2) tip
+C default
+C file2
+% on branch1, so no file1 and file2:
+0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+f1c642b1d8e5 (branch1)
+C default