cvs2git reports a "sprout" from a nonexistent commit?

There are a couple of weird-looking commits way back near the beginning
of the converted Postgres history:


commit 91f2ac21a1e085dfe81aae110cee2246a803f600    refs/tags/Release_2_0_0
Author: PostgreSQL Daemon <webmaster@postgresql.org>
Date:   Sat Aug 17 06:41:11 1996 +0000
   This commit was manufactured by cvs2svn to create tag 'Release_2_0_0'.      Sprout from Release_1_0_3 1996-08-02
01:24:01UTC PostgreSQL Daemon <webmaster@postgresql.org> 'This commit was manufactured by cvs2svn to create branch
'Release_1_0_3'.'  Cherrypick from master 1996-08-17 06:41:10 UTC Marc G. Fournier <scrappy@hub.org> 'changed missed
err()change to err_out()':       src/test/regress/Makefile       src/Makefile.global
src/interfaces/libpq/fe-misc.c      ... lots more files ...
 


commit a8b8a4c98c975a6e4e7f378168fc39b05831e09d    refs/tags/Release_2_0
Author: PostgreSQL Daemon <webmaster@postgresql.org>
Date:   Wed Aug 14 16:44:52 1996 +0000
   This commit was manufactured by cvs2svn to create tag 'Release_2_0'.      Sprout from Release_1_0_3 1996-08-02
01:24:01UTC PostgreSQL Daemon <webmaster@postgresql.org> 'This commit was manufactured by cvs2svn to create branch
'Release_1_0_3'.'  Cherrypick from master 1996-08-14 16:44:51 UTC Marc G. Fournier <scrappy@hub.org> '|':
src/backend/storage/ipc.h      src/test/regress/Makefile       src/Makefile.global       src/interfaces/libpq/fe-misc.c
     ... lots more files ...
 


What is weird about them is that the referenced "sprout" commit doesn't
exist.  Is this expected behavior?
        regards, tom lane