Lupdate skips during processing files included from other files

lupdate ignores content of file if it is included from other file that is earlier on list of files to process.

:~/lupdatetest$ /usr/local/Qt-4.6.2/bin/lupdate A.h B.h -ts x.ts
Updating 'x.ts'...
Found 2 source text(s) (0 new and 2 already existing)

:~/lupdatetest$ /usr/local/Qt-4.6.2/bin/lupdate B.h A.h -ts x.ts
Updating 'x.ts'...
Found 1 source text(s) (0 new and 1 already existing)
Kept 1 obsolete entries

:~/lupdatetest$ /usr/local/Qt-4.5.3/bin/lupdate A.h B.h -ts x.ts
Updating 'x.ts'...

Found 2 source text(s) (0 new and 2 already existing)

:~/lupdatetest$ /usr/local/Qt-4.5.3/bin/lupdate B.h A.h -ts x.ts
Updating 'x.ts'...

Found 2 source text(s) (0 new and 2 already existing)